General, Organic, & Biological Chemistry PDF

Chapter 1 Basic Concepts About Matter  Section 1.1 Chemistry: The Study of Matter Chemistry Field of study concerned with the characteristics, composition, and transformations of matter...

Chapter 1 Basic Concepts About Matter  Section 1.1 Chemistry: The Study of Matter Chemistry Field of study concerned with the characteristics, composition, and transformations of matter Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 2  Section 1.1 Chemistry: The Study of Matter Matter Anything that has mass and occupies space – Mass - Amount of matter present in a sample Includes naturally occurring living and nonliving things and synthetic materials – Examples: Plants, soil, rocks, air, bacteria, plastics Forms of energy such as heat, light, and electricity are not considered to be matter Universe is composed entirely of matter and energy Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 3  Section 1.2 Physical States of Matter Classification is based on whether the shape and volume of the matter sample are definite or indefinite – Solid – Liquid – Gas Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 4  Section 1.2 Physical States of Matter Solid Characterized by a definite shape and a definite volume Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 5  Section 1.2 Physical States of Matter Liquid Characterized by an indefinite shape and a definite volume Takes the shape of its container to the extent that it fills the container Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 6  Section 1.2 Physical States of Matter Gas Characterized by an indefinite shape and volume Completely fills its container, adopting both the container’s volume and its shape Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 7  Section 1.2 Physical States of Matter Figure 1.1 - A Comparison of the Volume and Shape Characteristics of Solids, Liquids, and Gases Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 8  Section 1.2 Physical States of Matter State of matter of a particular substance depends on: – Temperature – Surrounding pressure – Strength of the forces holding its structural particles together Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 9  Section 1.3 Properties of Matter Property Distinguishing characteristic of a substance that is used in its identification and description – Each substance has a unique set of properties that distinguishes it from all other substances Types – Physical – Chemical Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 10  Section 1.3 Properties of Matter Physical Property Characteristic that can be observed without changing the basic identity of a substance – Includes color, odor, physical state, melting point, boiling point, and hardness Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 11  Section 1.3 Properties of Matter Concept Check To measure the boiling point of a substance, a liquid must be changed into a gas. Why is boiling point considered a physical property when a gas’ appearance is much different from that of a liquid? Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 12  Section 1.3 Properties of Matter Concept Check To measure the boiling point of a substance, a liquid must be changed into a gas. Why is boiling point considered a physical property when a gas’ appearance is much different from that of a liquid? Although the appearance is different, the substance is still the same. Its chemical identity remains the same irrespective of the physical state. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 13  Section 1.3 Properties of Matter Chemical Property Characteristic that describes the way a substance undergoes or resists change to form a new substance – Example: Copper objects turn green in air Changes result from the reaction of a substance with one or more other substances – Decomposition - Change triggered by the presence of energy Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 14  Section 1.3 Properties of Matter Figure 1.3 - Chemical Property of Copper Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 15  Section 1.4 Changes in Matter Physical Change Process in which a substance changes its physical appearance but not its chemical composition Does not lead to the formation of a new substance – Example: Boiling or freezing water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 16  Section 1.4 Changes in Matter Chemical Change Process in which chemical composition of a substance changes Involves conversion of material(s) into one or more new substances – Example: Rusting of iron objects left exposed to moist air Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 17  Section 1.4 Changes in Matter Use of the Term Physical Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 18  Section 1.4 Changes in Matter Use of the Term Chemical Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 19  Section 1.4 Changes in Matter Concept Check Which one of the following is an example of a chemical change? a. Pulverizing (crushing) rock salt b. Burning of wood c. Dissolving of sugar in water d. Melting a popsicle on a warm summer day Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 20  Section 1.4 Changes in Matter Concept Check Which one of the following is an example of a chemical change? a. Pulverizing (crushing) rock salt b. Burning of wood c. Dissolving of sugar in water d. Melting a popsicle on a warm summer day Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 21  Section 1.5 Pure Substances and Mixtures Pure Substances Versus Mixtures Pure substance: Single kind of matter that cannot be separated into other kinds of matter by any physical means – Example: Water or sucrose Mixture: Physical combination of two or more pure substances – Each substance retains its own chemical identity – Example: Salt water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 22  Section 1.5 Pure Substances and Mixtures Mixtures Have variable composition Heterogeneous mixture: Contains visibly different phases, each of which has different properties Homogeneous mixture: Contains only one visibly distinct phase, which has uniform properties throughout Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 23  Section 1.5 Pure Substances and Mixtures Figure 1.6 - Pure Substances and Mixtures Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 24  Section 1.6 Elements and Compounds Element Pure substance that cannot be broken down into simpler pure substances by chemical means such as a chemical reaction, an electric current, heat, or a beam of light – Example: Gold, silver, copper Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 25  Section 1.6 Elements and Compounds Compound Pure substance that can be broken down into two or more simpler pure substances by chemical means – Example: Water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 26  Section 1.6 Elements and Compounds Figure 1.7 - A Pure Substance can be an Element or a Compound Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 27  Section 1.6 Elements and Compounds Distinguishing Between Compounds and Mixtures Compounds Mixtures Have properties distinctly Components retain their different from those of the individual properties substances that combined to form the compound Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 28  Section 1.6 Elements and Compounds Distinguishing Between Compounds and Mixtures Compounds Mixtures Have a definite chemical Have a variable chemical composition composition Components cannot be Physical methods are separated by physical sufficient to separate the methods components – Chemical methods are required Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 29  Section 1.6 Elements and Compounds Figure 1.8 - Classifying a Sample of Matter Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 30  Section 1.6 Elements and Compounds Questions Asked to Classify a Sample of Matter Does the sample of matter have the same properties throughout? Are two or more different substances present? Can the pure substance be broken down into simpler substances? Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 31  Section 1.7 Discovery and Abundance of the Elements 118 known elements – 88 of the elements occur naturally – 30 of the elements have been synthesized Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 32  Section 1.7 Discovery and Abundance of the Elements Figure 1.10 - Abundance of Elements (in Atom Percent) in the Universe Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 33  Section 1.7 Discovery and Abundance of the Elements Figure 1.10 - Abundance of Elements (in Atom Percent) in the Earth’s Crust Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 34  Section 1.8 Names and Chemical Symbols of the Elements Chemical Symbol One- or two-letter designation for an element derived from the element’s name – Two letter symbols can be the first two letters of the element’s name – First letter of a chemical symbol is always capitalized and the second is not H – Hydrogen Ba – Barium Co – Cobalt Pb – Lead Ag – Silver Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 35  Section 1.8 Names and Chemical Symbols of the Elements Chemical Symbol Some elements have symbols that were derived from non-English names – Ag – Silver – Au – Gold – Fe – Iron – Pb – Lead – Cu – Copper Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 36  Section 1.9 Atoms and Molecules Atom Smallest particle of an element that can exist and still have the properties of the element Limit of chemical subdivision – 254 million atoms arranged in a straight line would extend a distance of approximately 1 inch Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 37  Section 1.9 Atoms and Molecules Molecule Group of two or more atoms that functions as a unit because the atoms are tightly bound together Behaves as a single, distinct particle Limit of physical subdivision Diatomic molecule: Contains two atoms Triatomic molecule: Contains three atoms Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 38  Section 1.9 Atoms and Molecules Homoatomic Molecule All atoms present are of the same kind Substance containing homoatomic molecules must be an element Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 39  Section 1.9 Atoms and Molecules Heteroatomic Molecule Two or more kinds of atoms are present Substances containing heteroatomic molecules must be compounds Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 40  Section 1.9 Atoms and Molecules Figure 1.13 - Heteroatomic Molecules Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 41  Section 1.9 Atoms and Molecules Which of the following statements is true? a. The smallest particle of an element that can exist and still have properties of the element is called an atom. b. A group of two or more atoms that function as a unit form a molecule. c. Some classifications of molecules are: diatomic, homoatomic, and heteroatomic. d. All of these. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 42  Section 1.10 Chemical Formulas Notation made up of the chemical symbols of: – Elements present in a compound – Numerical subscripts Indicate the number of atoms of each element present in a molecule of the compound Examples – H2O - Two atoms of hydrogen, one atom of oxygen – Ca3(PO4)2 - Three atoms of calcium, two atoms of phosphorus, eight atoms of oxygen Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 43  Chapter 1 Review questions Chapter 1 1. Which of the following is a property of both gases and liquids? a. Definite shape b. Indefinite shape c. Definite volume d. Indefinite volume 2. When a substance undergoes a chemical change it is always true that a. it liquifies b. it changes from a solid to a gas c. it is converted to a new kind of matter with a different composition d. the temperature of the substance increases 3. The description "two substances present, two phases present" is correct for a. heterogeneous mixtures b. homogeneous mixtures c. elements d. compounds 4. Which of the following statements is correct? a. Elements, but not compounds, are pure substances. b. Compounds, but not elements, are pure substances. c. Both elements and compounds are pure substances. d. Neither elements nor compounds are pure substances. 5. An element is a substance that a. can be broken down into simpler substances by physical means. b. cannot be broken down into simpler substances by physical means. c. can be broken down into simpler substances by chemical means. d. cannot be broken down into simpler substances by chemical or physical means. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 44  Chapter 1 Review questions 6. Which of the following statements concerning the known elements is correct? a. No new elements have been identified within the last 40 years. b. Most elements occur naturally. c. 108 elements are known at present. d. Scientists have synthesized all possible non-natural elements. 7. The most abundant elements in the universe and in the Earth's crust are, respectively, a. oxygen and iron. b. hydrogen and helium. c. helium and carbon. d. hydrogen and oxygen. 8. In which of the following sequences of elements does each element have a two-letter chemical symbol? a. barium, iron, nitrogen b. selenium, nickel, strontium c. silicon, zinc, hydrogen d. iodine, xenon, titantium 9. In which of the following pairs of chemical formulas do both formulas represent compounds? a. O2 and O3 b. CO2 and O2 c. HCN and N2 d. N2O4 and NO2 10. Which of the following is a correct description of a sample of ice cubes in water? a. One phase present, one substance present b. One phase present, two substances present c. Two phases present, one substance present d. Two phases present, two substances present 11. A substance has a freezing point of -20°C. This is an example of a: a. physical property. b. chemical property. c. physical change. d. chemical change. 12. Which of the following substances is both homoatomic and tetraatomic? a. HCN b. H2O2 c. P4 d. H2CO3 Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 45