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Chemistry in Our Life © 2015 PEARSON EDUCATION, INC. 1  Discuss Discuss the what is chemistry and differentiate chemicals from not chemicals Objectives Iden...

Chemistry in Our Life © 2015 PEARSON EDUCATION, INC. 1  Discuss Discuss the what is chemistry and differentiate chemicals from not chemicals Objectives Identify Identify the connections of chemistry with other In this lesson disciplines students will Describe Describe the scientific method and apply it to real- life examples.  What is chemistry? Chemistry is the study of matter and changes that it undergoes. It is the study of elements, the compounds that they form and the reactions that they undergo. FROM: CHEMISTRY: MATTER AND ITS CHANGES BY JAMES E. BRADY AND FREDERICK A. SENESE (DEC 2007). COPYRIGHT 2007 BY CONCISE BOOKS PUBLISHING LLC 4  Matter is defined as anything that What is occupies space and has mass. Matter? © 2015 PEARSON EDUCATION, INC. 5 Chemistry Virtually everything around you is composed of chemicals. © 2015 PEARSON EDUCATION, INC. 6 Chemicals SUBSTANCES THAT HAVE THE SAME COMPOSITION AND PROPERTIES WHEREVER FOUND © 2015 PEARSON EDUCATION, INC. 7 Chemistry and Other Disciplines The Scientific Method: How Chemists Think Ways to Understand the World: Chemists use the scientific method—a way of learning that emphasizes observation and experimentation— to produce knowledge as the result of the senses. © 2015 PEARSON EDUCATION, INC. 9 Think Instructions: Read the story titled "The Blind Men and the Elephant" by J. G. Saxe adapted to a song by Natalie Merchant, you can also find the lyrics here: The Elephant: John Godfrey Saxe (1816- 1887). Next, identify each man observation and then describe the main challenges that these men face in collecting data and explain what each of them believed the elephant represent. Then, discuss how do you think the scientific method relates to the lyrics. Requirements: Identify each men conclusions. In your opinion, what are the problem with them?. Give a valid and well-explained reason for your opinion. Discuss how this poem/song illustrate the importance of the scientific method. The Scientific Method Observations involve measuring or observing some aspect of nature. Hypotheses are tentative interpretations of the observations. Laws summarize the results of a large number of observations. Theories are models that explain and give the underlying causes for observations and laws. Experiments are highly controlled observations © 2015 PEARSON EDUCATION, INC. 11  Observation of Combustion A N TO I N E L AV O I S I E R ( 1 7 4 3 – 1 7 9 4 ) , A F R E N C H C H E M I S T, M A D E A N O B S E RVAT I O N A B O U T T H E P H Y S I C A L W O R L D. © 2015 PEARSON EDUCATION, INC. 12  “The word "observation" has two meanings in the scientific method. First, there is the scientist’s observation of the world as it leads to hypothetical theory. This is the first step of the scientific method and can be presented in two ways, either as a natural observation or a staged one. Second, in the collection of data in an experiment using the scientific method, there are two types of observations, qualitative and quantitative”. OBSERVATIONS TYPES OF OBSERVATION IN THE SCIENTIFIC METHOD,. BY DANIEL FRANCIS. SCIENCING, APRIL 17, 2017. HTTPS://SCIENCING.COM/STEPS-PROCEDURES-CONDUCTING-SCIENTIFIC-RESEARCH-6900127.HTML 13  Using the Scientific Method Through your observations, you may determine that you are allergic to cat hair and dander. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Using the Scientific Method Suppose you visit a friend in her home, and soon after you arrive, you begin to sneeze. You observe that your friend has a new cat. You ask yourself why you are sneezing and form a hypothesis that you are allergic to cats. You perform experiments to test your hypothesis by visiting other friends with cats. If you sneeze after leaving the other homes with cats, you come to the conclusion that your hypothesis is correct. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. The Scientific Method: Overview © 2015 PEARSON EDUCATION, INC. 16 Scientific Method “Achievement”: The Atomic Theory The atomic theory of John Dalton (1766– 1844) Dalton explained the law of conservation of mass by proposing that all matter was composed of small, indestructible particles called atoms. Dalton’s theory was a model of the physical world—it went beyond the laws and observations of the time to explain these laws and observations. © 2015 PEARSON EDUCATION, INC. 17  Basic Math Skills Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Objectives By the end of this lesson student will be able To identify place value. To solve equations involving positive and negative numbers. To calculate percentages. To rewrite numbers using standard and scientific notation To perform calculation using power of ten without using a calculator To draw and interpret linear graph Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. This Photo by Unknown Author is licensed under CC BY-SA-NC  Place Values Place value is the value represented by a digit in a number on the basis of its position in the number. 1012-010 1-0x103 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Multiplication and Division of Positive and Negative Numbers 1. When two positive numbers or two negative numbers are multiplied or divided, the answer is positive (+). 2. When a positive number and a negative number are multiplied or divided, the answer is negative. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Addition of Positive and Negative Numbers 1. When two positive numbers are added, the answer is positive. When two negative numbers are added, the answer is negative. 2. When a positive number and a negative number are added, the smaller number is subtracted from the larger number and the result has the same sign as the larger number. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Subtraction of Positive and Negative Numbers When two numbers are subtracted, change the sign of the number to be subtracted. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Calculator Operations Get to know your own calculator and practice. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  C. Calculating a · / =10. Percentage - x100 10 To determine a percentage, divide the parts by the total (whole) and multiply by 100%. i 100 If the percentage of red balls is 5, there are 5 red balls in every 100 balls. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solving Equations Equations can be rearranged to solve for an unknown variable. 2x + 8 = 14 1. Place all like items on one side. Subtract 8 from each side: 2x + 8 – 8 = 14 – 8 2x =6 2. Isolate the variable you need to solve for. Divide both sides by 2: 3. Check your answer. 2(3) + 8 = 6 + 8 = 14 Your answer x = 3 is correct Solving Equations Equations can be rearranged to solve for an unknown variable. 2x + 8 = 14 1. Place all like items on one side. Subtract 8 from each side: 2x + 8 – 8 = 14 – 8 2x =6 2. Isolate the variable you need to solve for. Divide both sides by 2: 3. Check your answer. 2(3) + 8 = 6 + 8 = 14 Your answer x = 3 is correct  Study Solve the following equation for P1. Check P1V1 = P2V2 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Chapter 2 Readiness Key Math Skills Identifying Place Values (1.4A) Using Positive and Negative Numbers in Calculations (1.4B) Calculating a Percentage (1.4C) Writing Numbers in Scientific Notation (1.4F) Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Objectives By the end of this lesson, students will be able to Identify a number as measured or exact and to determine the Identify number of significant figures in a measured number. Solve Solve calculations using the correct number of significant figures. Identify and memorize the names of the units and the prefixes used Identify and for the US., metric, and SI units used in measurements of length, memorize volume, mass, temperature, and time. Construct Construct conversion factor to solve problems. Calculate the density of a substance; use the density to calculate Calculate the mass or volume of a substance. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Exact Numbers and Measured Numbers Exact numbers are the numbers are defined numbers, like a dozen or seconds in a minute, or they are obtained when you count a things. Measured numbers are the numbers obtained when you measure a quantity such as your height, weight, or temperature. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check Indicate whether each of the following is a measured or an exact quantity a measure A. 45 pens E. 12 gal B. aut 60 second in a minute exact F. 4 quart in one gallon was measure C. 20 roses G. 225 miles meane D. 5.43 g H. 0.0125 kg Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. This Photo by Unknown Author is licensed under CC BY-NC  This Photo by Unknown Author is licensed under CC BY-SA Chemistry: This An Introduction Photo by Unknown tounder Author is licensed General, Organic, This CC BY-SA-NC andPhoto Biological Chemistry, by Unknown Twelfth Author is licensed underEdition CC BY-SA © 2015 Pearson Education, Inc. International systemene met Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  The metric system is the standard system of measurement used in chemistry. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Units of Measurement, Metric and SI intea rnatione Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check Identify the SI units for each of the following: A. volume B. mass C. length D. temperature Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Reporting a Measurement When measuring: observe the numerical values of marked lines estimate value of the numbers between marks use the estimated number as the final number in your measured number Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Measured Numbers and Significant Figures Length is measured by observing the marked lines at the end of a ruler. The last digit in your measurement is an estimate, obtained by visually dividing the space between the marked lines. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Writing Measured Numbers for Length 16-vestimate / 1 59. em WT I eotmaon Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  X or - the number of Fewer significant number + or -= the number with Feuer decimals In a measured number, the significant figures (SFs) are all the digits including the estimated digit. Significant Figures Significant figures are used to represent the amount of error associated with a measurement Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  192-6 3 significant diets Dagnificant digeto - vo2 - 3 agnicant digits 20121 112 0 -o significant digits +. NO 1120 (no tenePanto al Final) = 3 agnificante Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check Identify the significant and nonsignificant zeros in each of the following numbers, and write each number in the correct scientific notation. A. 0.002 650 m -o O diget B. 43.026 g Jorget C. 1 044 000 L -digit Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Exact Numbers do not Count for SFs Recall that exact numbers are are not measured and do not have a limited number of significant figures numbers obtained by counting 8 cookies in definitions that compare two units 1 kg = 1 000 g in the same measuring system 1 qt = 4 cups Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Identify the numbers below as measured or exact and give the number of significant figures in each measured number. exact (no orget A. 3 coins g. B. The diameter of a circle is 7.902 cm. ↓ orget meanres , C. 60 min = 1 h exact (no eg diget). measured numbers Significant digit only in Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Rules for Rounding Off 1.If the first digit to be 2.If the first digit to be dropped is 4 or less, then dropped is 5 or greater, it and all the following then the last retained digits are dropped from digit of the number is the number. increased by 1. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Examples of Rounding Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Write the correct value when 3.1457 g is rounded to each of the following: A. three significant figures 3 159. 3 1 B. two significant figures g. 6700. -- 251g dig 6700 6. + x 183 0. 00311-8 ↑ eg dig ↓ memor de S se mantiens 0 003. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Multiplication and Division, Measured Numbers In multiplication or division, the final answer is written so that it has the same number of significant figures (SFs) as the measurement with the fewest => significant figures. Example 1 Multiply the following measured numbers: 24.66 cm × w 0.35 cm = 8.631 (calculator display) u 20se escribe el que agnificant menor co e - 2 = 8.6 cm (two significant figures) N ↳ Multiplying four SFs by two SFs gives us an answer with two SFs. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Multiplication and Division with SFs Example 2 Multiply and divide the following measured numbers: Multiplying three SFs by two SFs gives us an answer with two SFs. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Adding Significant Zeros Adding Zeros: When the calculator display contains fewer SFs than needed, add one or more significant zeros to obtain the correct number of significant figures. > Example 1 Multiply and divide the following measured numbers: Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Perform the following calculation of measured numbers. Give the answer in the correct number of significant figures. ② 38. 52cm 2 8. Som Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Addition and Subtraction with SFs In addition or subtraction, the final answer is written so that it has the same number of decimal places as the measurement with the fewest decimal places. - Example 1 Add the following measured numbers: 2.012 um Thousandths place 3 61.09 Hundredths place + 3.0~ Tenths place 66 102. ↳ 66. 1 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Addition and Subtraction with SFs In addition or subtraction, the final answer is written so that it has the same number of decimal places as the measurement with the fewest decimal places. Example 1 Add the following measured numbers: 2.012 Thousandths place 61.09 Hundredths place + 3.0 Tenths place 66.102 Calculator display 66.1 Answer, rounded to the tenths place Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Addition and Subtraction with SFs Example 2 Subtract the following measured numbers: 65.09 Hundredths place Tenths place 62 09. ↳ 62 1. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Addition and Subtraction with SFs Example 2 Subtract the following measured numbers: 65.09 Hundredths place Tenths place 62.09 Calculator display 62.1 Answer, rounded to the tenths place Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Add the following measured numbers: 82.409 mg + 22.0 mg 104 +09 my. 10t. Img Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. 2.4 Prefixes and Equalities Using a retinal camera, an ophthalmologist photographs the retina of the eye. Learning Goal Use the numerical values of prefixes to write a metric equality. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Units of Measurement— Metric System Prefixes Imm = 1x103m Please tell grandman Don't More Kittens chare Me My , Fal, Prefixes convert always the base units into units thatzoging are appropriate for common usage or appropriate measure. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Prefixes and Equalities The relationship of a prefix to a unit can be expressed by replacing the prefix with its numerical value. For example, when the prefix kilo in kilometer is replaced with its value of 1000, we find that a kilometer is equal to 1000 meters. kilometer = 1000 meters kiloliter = 1000 liters kilogram = 1000 grams Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Daily Values for Selected Nutrients The U.S. Food and Drug Administration uses metric prefixes to express amounts of daily nutrient requirements. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Fill in the blanks with the correct prefix. R A. 1000 m = 1 ___m Study Check B. 1 × 10 g = 1 ___g M C C. 0.01 m = 1 ___m Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Measuring Length Ophthalmologists measure the diameter of the eye’s retina in centimeters (cm), while a surgeon measures the length of a nerve in millimeters (mm). Each of the following equalities describes the same length in a different unit: 1 m = 1000 1 m = 100 cm 1 cm= 10 mm mm = 1 × 10 = 1 × 102 cm = 1 × 101 mm mm Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. The Cubic Centimeter ↑ cm3 = Im/ (P(c) 1 cm3 = 1 cc = 1 mL 10 cm × 10 cm × 10 cm = 1000 cm3 = 1000 mL = 1 L Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Identify the larger unit in each of the following: A. mm- or cm smaller number B. kilogram or centigram C.OmL or L D. O kL or mcL Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Solution Identify the larger unit in each of the following: A. mm or cm A millimeter is 0.001 m, smaller than a centimeter, 0.01 m. B. kilogram or centigram A kilogram is 1000 g, larger than a centigram, 0.01 g. C. mL or L A milliliter is 0.001 L, larger than a microliter, 0.000 001 L. D. kL or mcL A kiloliter is 1000 L, larger than a microliter, 0.000 001 L. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Review Metric System: units and Prefixes Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Example Measuring Length Ophthalmologists measure the diameter of the eye’s retina in centimeters (cm), while a surgeon measures the length of a nerve in millimeters (mm). Each of the following equalities describes the same length in a different unit: 1 m = 1000 1 m = 100 cm 1 cm= 10 mm mm = 1 × 10 = 1 × 102 cm = 1 × 101 mm mm Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Writing Conversion Factors In the United States, the contents of many packaged foods are listed in both U.S. and metric units. Learning Goal Write a conversion factor for two units that describe the same quantity. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Equalities Equalities use two different units to describe the same measured amount are written for relationships between units of the metric system, U.S. units, or between metric and U.S. units For example, 1m = 1000 mm 1 lb = 16 oz 2.20 lb = 1 kg Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Equalities: Conversion Factors Any equality can be written as fractions called conversion factors. Conversion Factors for the Equality 60 min = 1 h Conversion Factors for the Metric Equality 1 m = 100 cm Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Some Common Equalities ↳ Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check Write conversion factors from the equality for each of the following: A. liters and milliliters ⑨ I B. meters to inches ⑧ Stem 10- 2. ↑ = in m cm = 1 x C. meters and kilometers my m m ① m -- km 1 km = 1000 m m Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solution Write conversion factors from the equality for each of the following: A. B. C. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Conversion Factors in a Problem A conversion factor may be stated within a problem that applies only to that problem is written for that problem only Write the CF: The car was traveling at 85 km/h. Write the CF: One tablet contains 500 mg of vitamin C. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Conversion Factors: Dosage Problems Write the conversion factors: Keflex (Cephalexin), an antibiotic used for respiratory and ear infections, is available in 250-mg capsules. The 250 mg is measured: It has two significant figures. The 1 in 1 capsule is an exact number. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Conversion Factors: Percentages Example: A person might have 18% body fat by mass. The thickness of the skin fold at the abdomen is used to determine the percentage of body fat. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check Write the equality and its corresponding conversion factors, and identify each number as exact or give its significant figures for the following statement: Salmon contains 1 9 gOFA Salmon 1.9% omega- 1009 =. of Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. 2.6 Problem Solving Using Unit Conversions Learning Goal Use conversion factors to change from one unit to another. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solving Problems Using Conversion Factors Example: If a person weighs 164 lb, what is the body mass in kilograms? STEP 1 State the given and needed quantities. 60x6 STEP 2 Write a plan to convert the given unit to the needed unit. 1 m = worm pounds kilograms gram 1kgETog 1000 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solving Problems Using Conversion Factors Example: If a person weighs 164 lb, what is the body mass in kilograms? STEP 3 State the equalities and conversion factors. STEP 4 Set up the problem to cancel units and calculate the answer. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check A rattlesnake is 2.44 m long. How many centimeters long is the snake? 2. 44mxcm = 244 Im k Am = 100cm - 100 · m Im = 1000mm Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solution A rattlesnake is 2.44 m long. How many centimeters long is the snake?. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Using Two or More Conversion Factors A doctor’s order prescribed a dosage of 0.150 mg of Synthroid. If tablets in stock contain 75 mcg of Synthroid, how many tablets are required to provide the prescribed medication? STEP 1 State the given and needed quantities. ANALYZE GIVEN NEED THE PROBLEM 0.150 mg Synthroid number of tablets STEP 2 Write a plan to convert the given unit to the needed unit. milligrams micrograms number of tablets Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solving Problems Using Conversion Factors Example: A doctor’s order prescribed a dosage of 0.150 mg of Synthroid. If tablets in stock contain 75 mcg of Synthroid, how many tablets are required to provide the prescribed medication? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check How many minutes are in 1.4 days? 1. y 2016 m min Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition & min © 2015 Pearson Education, Inc. Solution How many minutes are in 1.4 days? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Study Check If your pace on a treadmill is 65 meters per minute, how many minutes will it take for you to walk a distance of 7.5 kilometers? 2x102 & - 1. * Skmxml Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Solution If your pace on a treadmill is 65 meters per minute, how many minutes will it take for you to walk a distance of 7.5 kilometers? - Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Prm 2.7 Density 1000m ↑ I m & 100 cm Objects that sink in water are more dense than water; objects that float are less dense. Learning Goal Calculate the density of a substance; use the density to calculate the mass or volume of a substance. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Densities of Common Substances Insert table 2.9 page 46 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Density Density compares the mass of an object to its volume. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Volume by Displacement A solid completely submerged in water displaces its own volume of water has a volume calculated from the volume difference = 9.5 cm3 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Density Using Volume Displacement The density of the zinc object is calculated from its mass and volume. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check What is the density (g/cm ) of a 48.0-g sample of a metal if the level of water in a graduated cylinder rises from 25.0 mL to mL after the metal is added? 33.0 mL 25.0 mL object Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Solution What is the density (g/cm3) of a 48.0-g sample of a metal if the level of water in a graduated cylinder rises from 25.0 mL to 33.0 mL after the metal is added? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Problem Solving Using Density HERE If the volume and the density of a sample are known, the mass in grams of the sample can be calculated by using density as a conversion factor. Core Chemistry Skill Using Density as a Conversion Factor Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Problem Solving Using Density Example: John took 2.0 teaspoons (tsp) of cough syrup for a cough. If the syrup had a density of 1.20 g/mL and there is 5.0 mL in 1 tsp, what was the mass, in grams, of the cough syrup? A. 0.083 g B. 2.0 g C. 12.0 g D. 24. 0 g Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Problem Solving Using Density Example: John took 2.0 teaspoons (tsp) of cough syrup for a cough. If the syrup had a density of 1.20 g/mL and there is 5.0 mL in 1 tsp, what was the mass, in grams, of the cough syrup? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Specific Gravity Specific gravity (sp gr) is a relationship between the density of a substance and the density of water is calculated by dividing the density of a sample by the density of water, which is 1.00 g/mL at 4 °C is a unitless quantity A substance with a specific gravity of 1.00 has the same numerical value as the density of water (1.00 g/mL). Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Study Check An unknown liquid has a density of 1.32 g/mL. What is the volume of a 14.7-g sample of the liquid? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Solution mL. What is the volume (mL) of a 14.7-g sample of the liquid? Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Concept Map Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. STARTING WITH MATTER  OBJECTIVES By the end of this lesson, students will be able to: Define matter and for given examples, identify what is matter from what is not. Differentiate matter as pure substances or mixtures and identify examples. Identify and describe the common state of the matter. Differentiate physical and chemical properties. Define temperature, identify the different scales and calculate a corresponding temperature on another scale.  WHAT IS MATTER? Matter is defined as anything that occupies space and has mass. Each particular kind of matter is what we call substance. Everything that you can see in this room is made of matter. Water. Air. Desks.  Classification of Matter According to its composition: Coreourgeneu Mixtures contain two or -regar Pure substances have a more different pure fixed or definite substances that are composition. physically mixed but not chemically combined. othegold a one type of atom two or more elements uniform throughout different parts of the mixture are visible CLASSIFICATION OF MATTER Mixtures A mixture is a type of matter that consists of two or more substances that are physically mixed but not chemically combined two or more substances in different proportions substances that can be separated by physical methods A mixture of a liquid and a solid is separated by filtration. Study Check Identify each of the following as a pure substance or a mixture: A. pasta and tomato sauce misture B. aluminum foil Pure - C. helium Furt - D. air mixture - 02 + 202 Study Check Identify each of the following as a pure substance or a mixture: A. pasta and tomato sauce mixture B. aluminum foil pure substance C. helium pure substance D. air mixture Study Check Identify each of the following as a homogeneous or heterogeneous mixture: A. hot fudge sundae B. shampoo C. sugar water D. peach pie Study Check Identify each of the following as a homogeneous or heterogeneous mixture: A. hot fudge sundae heterogeneous mixture B. shampoo homogeneous mixture C. sugar water homogeneous mixture D. peach pie heterogeneous mixture STATES AND PROPERTIES OF MATTER The evaporation of water from seawater gives solid white crystals of salt called sodium chloride.  THE COMMON STATES OF MATTER: SOLID, LIQUID, AND GAS SOLIDS Table Salt is an example of Crystalline Solid The chemical formula that represents water is: NaCl Sodium Chloride Crystalline Amorphous Types of Solids  URINARY SEDIMENT This Photo by Unknown Author is licensed under CC BY-SA toxalate LIQUIDS WHY IS WATER ADOPT THE SHAPE OF ITS CONTAINER? Examples of liquids C3H8O H2O2 Hg Q: Pure substance or mixture? Element or compound?  Gases Particles: Are apart. Moving very fast Constantly colliding between them and against the walls. Molecule exerts a force when it collides with a surface. The result of many of these collisions is pressure THE AIR IS A MIXTURE OF GASES  Atoms or molecules pack close to each other in fixed locations. IN SOLIDS: Neighboring atoms or molecules may vibrate or oscillate, but they do not move around each other. Solids have fixed volume and rigid shape. In Liquids: particles that are close together, but mobile have a definite volume, but takes the shape of its container particles that move slowly In Gases particles that are far apart particles that move very fast A gas takes the shape and volume of its container. A COMPARISON OF SOLIDS, LIQUIDS, AND GASES Study Check Identify each description as that of particles of a 1) solid 2) liquid 3) gas __ A. has definite volume but takes the shape of the container __ B. particles are moving rapidly __ C. particles fill the entire volume of a container __ D. particles have a fixed arrangement __ E. particles are close together but moving randomly PHYSICAL PROPERTIES Physical properties include the shape, are characteristics physical state, boiling observed or measured and freezing points, without changing the density, and color of identity of a substance that substance Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition Copyright © 2012 by Pearson Education, Inc. EXAMPLE: PHYSICAL PROPERTIES OF COPPER Copper has these physical properties: reddish-orange color shiny excellent conductor of heat and electricity solid at 25 °C melting point 1083 °C boiling point 2567 °C Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition Copyright © 2012 by Pearson Education, Inc. Study Check Identify the state of matter for each of the following: A. vitamin tablets B. eye drops C. vegetable oil D. a candle E. air in a tire Physical Change A physical change occurs in a substance if there is a change in the state a change in the physical shape no change in the identity and composition of the substance EXAMPLES OF PHYSICAL CHANGES  Study Check Classify each of the following as a 1) change of state 2) change of shape A. chopping a log into kindling wood B. water boiling in a pot C. ice cream melting D. ice forming in a freezer E. cutting dough into strips CHEMICAL PROPERTIES Chemical properties describe the ability of a substance to interact with other substances to change into a new substance CHEMICAL CHANGES When a chemical change takes place, the original substance is turned into one or more new substances with new chemical and physical properties. Examples of Chemical Changes Insert table 3.4 page 63 Study Check Classify each of the following properties as physical or chemical: A. Ice melts in the sun. Thal B. Copper is a shiny metal. dugacal C. Paper can burn. chanical D. A silver knife can tarnish. chemical E. A magnet removes iron particles from a mixture. rhyacal Study Check Classify each of the following changes as physical or chemical: -othycal o physi c al A. burning a candle B. ice melting on the street - C. toasting a marshmallow -chemical D. cutting a pizza -physical E. iron rusting in an old car-schemical TEMPERATURE A digital ear thermometer is used to measure body temperature. TEMPERATURE ROY -NOT IS A MEASURE OF HOW HOT OR COLD AN OBJECT IS COMPARED TO ANOTHER OBJECT. This Photo by Unknown Author is licensed under CC BY-SA-NC  song 100% = 180F 12 = 1 8F k. +2= 253 FR-253 · - 253 k = 298 c · · 12250 lowest poside erung ORewin temperature = lees" "impossible de Temperature Scales  Study Check A. What is the temperature at which water freezes? 1) 0 °F 2) 0 °C 3) 0 K B. What is the temperature at which water boils? 1) 100 °F 2) 32 °F 3) 373 K C. How many Celsius units are between the boiling and freezing points of water? 1) 100 2) 180 3) 273 Fahrenheit and Celsius Scales On the Celsius scale, there are 100 degrees Celsius between the freezing and boiling points of water. On the Fahrenheit scale, there are 180 degrees Fahrenheit between the freezing and boiling points of water. 180 Fahrenheit degrees = 100 degrees Celsius  KELVIN TEMPERATURE SCALE TK = Tc + 273.15 Example: Solving a Temperature Problem A person with hypothermia has a body temperature of 34.8 °C. What is that temperature in degrees Fahrenheit? 1 8 : (30 8c). + 32 = 32 94 64 $2 +. 64 =. ↓ significant that 93F Answer: 94.6 °F counts Study Check On a cold winter day, the temperature is –15 °F. What is that temperature in degrees Celsius? °C °C °C -3 -°C - 26 8.  Learning Check What is normal body temperature of 37 °C in kelvins? A. 236 K B. 310 K C. 342 K D. 98.0 K Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  OBJECTIVES By the end of this lesson, students will be able to: Explain and given examples of energy. Identify types of energy and differentiate kinetic energy (KE) from potential energy (PE). Recognize energy unit and transform one unit into another unit (J, cal, Cal). Define calorie and calculate the number of calories needed to heat a mass of water by a defined number of ºC. Define nutrition calorie (Cal) and calculate the energy in different food. Use the energy values to calculate the kilocalories (kcal) or kilojoules (kJ) for a food. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ENERGY Energy makes objects move This Photo by Unknown Author is licensed under CC BY-SA makes things stop is defined as the ability to “do work” Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. This Photo by Unknown Author is licensed under CC BY-SA-NC  KINETIC ENERGY Kinetic energy is the energy of motion. swimming water flowing over a dam working out The movement of water that flows from the top of a dam is an example of Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition kinetic energy. © 2015 Pearson Education, Inc.  POTENTIAL ENERGY Potential energy is energy stored for use at a later time. water at the top of a dam a compressed spring chemical bonds in gasoline, coal, or food The water at the top of the dam has potential energy by virtue of its position. As the water falls over and down the dam, the potential energy is converted to kinetic energy. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK Identify the energy in each example as potential or kinetic: * always energy: moving storage cookie A. rollerblading - Kinetie -rotantial B. a peanut butter and jelly sandwich C. mowing the lawn Kunatic - D. gasoline in the gas tank - Potential Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Heat is the energy associated with the measured in joules or calories movement of particles The faster the particles move, the greater the heat or thermal energy of the substance. HEAT AND UNITS FOR ENERGY Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Energy is measured in joule (J) or in kilojoules (kJ), 1000 joules calories (cal) or in kilocalories (kcal), 1000 calories One calorie is defined as the amount of energy UNITS FOR needed to raise the temperature of 1 g of water by 1 °C. ENERGY Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ENERGY COMPARISON Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK How many calories are obtained from a pat of butter if it provides 150 J of energy when metabolized? Leal ISOjX = 35 85 A. 0.86 cal. 4. 184) 36 B. 630 cal I C. 36 cal Sacale 1000 cal = 0 036. kcal Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Dietitians specialize in helping others One hour of swimming uses 2100 kJ of learn about nutrition and the need for a energy. balanced diet. ENERGY AND NUTRITION Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CALORIMETER is used to measure heat transfer indicates the heat gained by water, which is the heat lost by a sample during combustion In a calorimeter, the burning of a food sample increases the temperature of water, which is used to calculate the energy value of the food. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ENERGY AND NUTRITION On food labels, energy is shown as the nutritional Calorie, written with a capital C. In countries other than the United States, energy is shown in kilojoules (kJ). 1 Cal = 1000 calories 1 Cal = 1 kcal The nutrition facts include the total Calories and kilojoules, and the grams of carbohydrate, fat, and protein per serving. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CALORIC FOOD VALUES Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. ENERGY VALUES FOR SOME FOODS Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK A cup of whole milk contains 13 g of carbohydrate, 9.0 g of fat, and 9.0 g of protein. How many kilocalories does a cup of milk contain? (Round the final answer to the tens place.) A. 50 kcal B. 80 kcal C. 170 kcal Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CHEMISTRY LINK TO HEALTH The number of kilocalories or kilojoules needed in the daily diet of an adult depends on gender, age, and level of physical activity. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  This Photo by Unknown Author is licensed under CC BY-SA-NC This Photo by Unknown Author is licensed under CC BY-SA SPECIFIC HEAT Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  At q m SH - =. SPECIFIC HEAT (SH) Capacity is the amount of heat that raises the temperature of exactly 1 g of a substance by exactly 1 °C it has units of J/g °C and of cal/g °C Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SPECIFIC HEATS OF SOME SUBSTANCES Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK we can -water A. cools 1. When ocean water cools, the B. warms & surrounding air C. stays the same 2. Sand in the desert is hot in the A. high specific heat day and cool at night. Sand must have a -B. low specific heat ↳ low heat calanty Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SOLUTION 1. When ocean water cools, the B. warms surrounding air 2. Sand in the desert is hot in the day and cool at night. Sand B. low specific heat must have a Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CALCULATIONS USING SPECIFIC HEAT ! SH-C -R Core Chemistry Skill Using the Heat Equation Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK What is the specific heat if 24.8 g of a metal absorbs 275 J of energy and the temperature rises from 20.2 °C to 24.5 °C? given = m = 28. 89 q = 2ST = 21 S1 - 20. 2) = 1 3C. 5 +t. At. = Ask = SH SH. At. m formular = q = H - Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CHANGES OF STATE Matter undergoes a change of state when it is converted from one state to another state. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  MELTING AND FREEZING Water has a freezing (melting) point of 0 °C. Melting and freezing are reversible processes. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  HEAT OF FUSION The heat of fusion is the amount of heat released when 1 g of liquid freezes (at its freezing point) is the amount of heat needed to melt 1 g of solid (at its melting point) For a given amount of substance, heat released during freezing = heat needed during melting Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  HEAT OF FUSION Heat of Fusion for Water To melt water, H2O(s) + 80. cal/g (or 334 J/g) H2O(l) To freeze water, H2O(l) H2O(s) + 80. cal/g (or 334 J/g) Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK How many kilojoules are needed to melt 32.0 g of ice at 0 °C? Answer: 10,700J Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  EVAPORATION, BOILING, AND CONDENSATION Water evaporates when molecules on the surface gain sufficient energy to form a gas condenses when gas molecules lose energy and form a liquid During evaporation, molecules of the liquid are converted to gas at the surface of the liquid. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  HEAT OF VAPORIZATION The heat of vaporization is the amount of heat absorbed to change 1 g of liquid to gas at the boiling point released when 1 g of gas changes to liquid at the boiling point Vaporization and condensation are reversible processes. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  HEAT OF VAPORIZATION Heat of Vaporization for Water (Boiling Point 100 °C ) Absorbed when 1 g of water changes to steam H2O(l) + 540 cal/g (or 2260 J/g) H2O(g) Released when 1 g of steam changes to water H2O(g) H2O(l) + 540 cal/g (or 2260 J/g) Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK How many kilojoules (kJ) are released when 50.0 g of steam from a volcano condenses at 100 °C? Answer: 113 kJ Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SUBLIMATION AND DEPOSITION When sublimation occurs, the particles on the surface of the solid change directly to a vapor there is no change in temperature Sublimation and deposition are reversible processes. When deposition occurs, gas particles change directly to a solid. Dry ice undergoes sublimation. Dry ice sublimes at –78 °C. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SUBLIMATION AND DEPOSITION Sublimation is used to prepare freeze-dried foods for long-term storage. Water vapor will change to solid on contact with a cold surface. Freeze-dried foods have a long shelf life because they contain no water.  HEATING CURVE On a heating curve, diagonal lines indicate changes in temperature for a physical state, and horizontal lines (plateaus) indicate changes of state. A heating curve diagrams the temperature increases and changes of state as heat is added. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  COOLING CURVE A cooling curve illustrates the changes of state as a gas is cooled uses sloped lines to indicate a decrease in temperature uses plateaus (flat lines) to indicate a change of state A cooling curve for water illustrates the change in temperature and changes of state as heat is removed. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CHALLENGE PROBLEM: COMBINED HEAT CALCULATIONS Calculate the total heat, in joules, needed to convert 15.0 g of liquid ethanol at 25.0 °C to gas at its boiling point of 78.0 °C. Ethanol has a specific heat of 2.46 J/g °C and a heat of vaporization of 841 J/g. Hint Answer: Total heat needed = 14 600 J Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK When a volcano erupts, 175 g of steam at 100.0 °C is released. How many kilojoules are lost when the steam condenses and then freezes at 0 °C ? A. 396 kJ B. 528 kJ C. 133 kJ Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CHALLENGE PROBLEM When a volcano erupts, 175 g of steam at 100.0 °C is released. How many kilojoules are lost when the steam condenses and then freezes at 0 °C ? Information needed: 175 g steam at 100.0 °C ice, at 0.0 °C heat vaporization, 2260 J/g specific heat, 4.184 J/ g °C heat fusion, 334 J/g Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  HINT: MAKE A PLAN 100.0 °C 0.0 °C Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Calculate the heat released as steam is condensed. Calculate temperature change of the liquid T = 100.0 ° °C = 100.0 °C Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Calculate the heat released as liquid is cooled. Calculate the heat released as liquid freezes. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Calculate the total energy needed. Heat released as steam is condensed = 396 000 J Heat released as liquid is cooled = 73 200 J Heat released as liquid freezes = 58 500 J Total heat needed = 528 000 J Answer is B. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  CONCEPT MAP Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  1 ATOMS AND ELEMENTS Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Stating the symbol and naming the first 20 elements as well as other selected elements on the Periodic table. Identifying elemental families and periods in the Periodic table. Identifying elements as metals, nonmetals or metalloids according to their position in the periodic table. Identifying subatomic particles by charge, relative mass and location within the atom. OBJECTIVES Predicting elements by symbol or name, when any two of the following properties of the element are given (ie: atomic number, mass number, number of protons, number of neutrons and number of electrons). Predicting whether atoms are isotopes of the same element when given atomic number and atomic masses. Generating the electronic configuration of the ground state for the first 20 elements in the Periodic table Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  4.1 ELEMENTS AND SYMBOLS 3 Elements are pure substances from which all other things are built cannot be broken down into simpler substances are listed on the inside front cover of this text Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SOME ELEMENTS AND THEIR NAMES Element names come from planets, mythological figures, 4 minerals, colors, geographic locations, and famous people. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. 5 20ctements NAMES AND SYMBOLS: COMMON ELEMENTS Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK Give the names of the elements with the following symbols: A. P B. Al C. Mn #Hg D. H E. K 6 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  4.2 THE PERIODIC TABLE The periodic table · & O hom organizes 118 elements into groups with similar properties and places them in order of increasing atomic mass. & F Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition · © 2015 Pearson Education, Inc. Ca = 152520933383152 een que Unico ~ -  GROUPS AND PERIODS Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  NAMES OF GROUPS Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  METALS, NONMETALS, AND METALLOIDS AND THE PERIODIC TABLE ↳ nonmetal number one n Insert figure 4.6 page 102 Li metaf Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Metals are shiny and ductile are good conductors of heat and electricity CHARACTERISTICS Nonmetals OF METALS, NONMETALS, AND are dull, brittle, and poor conductors METALLOIDS are good insulators Metalloids are better conductors than nonmetals but not as good as metals are used as semiconductors and insulators Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  COMPARING A METAL, NONMETAL, AND METALLOID Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK Identify each of the following elements as a metal, nonmetal, or metalloid. A. sodium metal B. chlorine nonmetal C. silicon metalloid D. iron rectal E. carbon Non metal Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  THE ATOM AN ATOM IS THE SMALLEST PARTICLE OF AN ELEMENT THAT RETAINS THE CHARACTERISTICS OF THAT ELEMENT. matter ligh is energy not Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  © 2015 Pearson Education, Inc. 15 Democritus suggested that if you divide matter into smaller and smaller pieces, you end up with tiny, indestructible particles. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  DALTON’S ATOMIC THEORY Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  © 2015 Pearson Education, Inc. 17 are tiny particles of matter of an element are similar to each other and different from those of other elements of two or more different elements combine to form compounds are rearranged to form new combinations in a chemical reaction Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  18 Atoms = Indivisible All atoms of an element = same mass atom/s A + atom/s B = Compound + = Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  20 Plum pudding model of the atom Cathod ray tube In the model, negatively charged electrons (yellow) were held in a sphere of positive charge (red). Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. © 2015 Pearson Education, Inc.  21 The Discover of the Atomic Nucleus the cover ton - golment d 1909: Rutherford To di Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. 22 RUTHENFORD’S ATOM All atoms have a nucleus and electrons Nucleus: - 99.9% of the total mass - small fraction of the total volume Electrons: - distributed in a large region - do not have much mass The atoms are mostly empty space Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STRUCTURE OF THE ATOM An atom consists of a nucleus that contains protons and neutrons electrons in a large, empty space around the nucleus Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ELECTRICAL CHARGES IN AN ATOM Atoms contain subatomic particles. Protons have a positive (+) charge. Electrons have a negative (–) charge. Neutrons are neutral. Like charges repel and unlike charges attract. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  Atomic Mass Unit MASS OF THE ATOM One atomic mass unit (amu) has a mass equal to one- twelfth of the mass of the carbon-12 atom. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  SUBATOMIC PARTICLES IN THE ATOM Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  27 SUMMARY ATOMIC THEORY Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK Which of the following subatomic particles fits each of the descriptions below? proton, neutron, electron A. found outside the nucleus B. has a positive charge C. has mass but no charge Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ATOMIC NUMBER = PROTONS IN AN ATOM Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  ATOMS ARE NEUTRAL For neutral atoms, the net charge is zero. number of protons = number of electrons Aluminum has 13 protons and 13 electrons. The net (overall) charge is zero. 13 protons (13+) + 13 electrons (13–) = 0 Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc.  STUDY CHECK Use the periodic table to fill in the atomic number, number of protons, and number of electrons for each of the following elements: Element Atomic Proto