Midterm Review (Revised F24).docx

Name \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Chemistry 152L ]** **[Midterm Review ]** 1. [**Definitions**:] Write the name that corresponds to each of the following definitions in the space provided. The degree of agreement among several measurements of th...

Name \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Chemistry 152L ]** **[Midterm Review ]** 1. [**Definitions**:] Write the name that corresponds to each of the following definitions in the space provided. The degree of agreement among several measurements of the same quantity. The reproducibility of a measurement. -- ---------------------------------------------------------------------------------------------------------------------------------------- The amount of heat required to raise the temperature of one gram of a particular substance by one-degree Celsius. Two or more atoms of the same element with the same atomic number nearly identical chemical behavior but with a differing mass number. A mixture consisting of dissimilar or diverse ingredients that are not evenly distributed throughout. 2. Write the correct chemical formulas, including the charge, for each of the following ions. Cation Name Formula Anion Name Formula -------------- --------- ------------ --------- Ammonium Sulfate Sodium ion Phosphate Aluminum ion Carbonate Calcium ion Nitrate 3. Complete the following table by providing the name and formula for each ionic compound. NO~3~^-^ CO~3~^2-^ Cl^-^ OH^-^ ---------- ---------- ----------- ------- ------- NH~4~^+^ Ba^2+^ Al^3+^ 4\. The enthalpy change for the reaction of hydrogen gas and oxygen gas to produce water is -285.8 kJ per mole of water formed. 2H~2~ + O~2~ - 2 H~2~O Δ H = -285.8 kJ a. Is this reaction exothermic or endothermic? b. Is energy absorbed by the system or released by the system? 5\. Write the ionic compound formed from the combination of the cations and anions below: a\. Pb^+4^ & SO~4~^-2^ b. Ca^+2^ & NO~3~^-^ c. Ba^+2^ & PO~4~^-3^ 6\. Name the three ionic compounds in question 5. a\. b. c. 7\. A sample of a liquid with a mass of 20.67 g was decomposed into its elements and gave 10.65 g of carbon, 3.547 g of hydrogen, and 6.473 g of oxygen. Calculate the percentage of oxygen in the sample. 8\. From the following list of substances and heat capacities, choose the one that will have the lowest temperature after absorbing 100.0kJ of heat. Assume that you begin at the same initial temperature and that you have identical masses of each of these 4 substances. Explain your reasoning. Material Specific Heat (J/g\*C) ---------- ------------------------ Lead 0.128 Copper 0.385 Ethanol 2.42 Water 4.18 9\. Air is 0.93% argon by volume. Find the volume of air that contains 682 mL of argon. 10\. A graduated cylinder containing water reads 29.9 mL. Upon addition of 48.937 grams of solid beads, the volume on the cylinder now reads 64.9mL. a\. What is the volume of the solid? b\. What is the density of the solid? **[Multiple Choice]**: Choose the single best answer to each question below. 1\. Suppose a thermometer has marks at every one-degree increment and the mercury level on the thermometer is exactly between the 25 and 26 degree Celsius marks. We should properly report the temperature measurement as A\) 25°C B\) 26°C C\) 25.5°C D\) 25.50°C E\) 25.55°C 2\. The correct number of significant figures in the number 0.002320 is: A\) 7 B\) 4 C\) 3 D\) ambiguous E\) none of the above 3\. The correct decimal representation of 1.201 × 10-7 is: A\) 12010000 B\) 0.0001201 C\) 0.0000001201 D\) 1201.000 E\) none of the above 4\. A student experimentally determines the specific heat capacity of a metal to be 5.88J/g^o^C. His instructor tells him that the true value is 7.21J/g^o^C. What is the percent difference? A\) 123% B\) 22.6% C\) 18.4% D\) 29.0% E\) 81.6% 5\. Which of the following statements is false? A\) When two liquids are immiscible, they will not mix with each other B\) Sodium is an alkali metal C\) Hexane is miscible with water D\) In the periodic table, a **Family** is a vertical column E\) In the periodic table, a **Group** is a vertical column 6\. Group 1A elements are also called: A\) noble gases. B\) halogens. C\) alkaline earth metals. D\) alkali metals. E\) none of the above 7\. Which of the following statements about the periodic table is false? A\) The noble gases, the least reactive of all elements, are located in the last vertical column to the far right of the table. B\) Each vertical column of the table contains elements with similar chemical and physical properties C\) Metals are generally located on the left side and nonmetals on the right D\) Elements in the same horizontal row of the table have similar physical characteristics E\) The alkali metals are located in the first vertical column at the far left of the table 8\. Which of these involves a chemical change? A\) boiling B) dissolving C) oxidation D) condensation 9\. How many hydrogen atoms are indicated by the formula (NH~4~)~2~C~6~H~8~O~2~? A\) 16 B) 8 C) 12 D) 14 E) 24 10\. The total number of oxygen atoms indicated by the formula Cu~3~(PO~4~)~2~ is ---- ---- A) 8 B) 4 C) 12 D) 16 E) 11 ---- ---- 11\. Convert: 38.6 L = \_\_\_\_\_\_\_\_\_\_\_\_\_ mL. ---- -------------------------- A) mL B)  mL C) mL D)  mL E) 3.86 mL ---- -------------------------- 12\. Convert: g = \_\_\_\_\_\_\_\_\_\_\_\_ kg. ---- -------------------------- A)  kg B) kg C)  kg D) kg E) 0.0344 kg ---- -------------------------- 13\. The number 3.00183 rounded to four significant figures is ---- --------------- A) 3.002 B) 3.001 C) 3.000 D) 3.183 E) none of these ---- --------------- 14\. How many significant figures are in the number 60.02 x 10^5^? ---- --------------- A) 2 B) 3 C) 4 D) 5 E) none of these ---- --------------- 15\. The number 14.809 rounded to three significant figures is ---- -------- A) 15.0 B) 14.9 C) 14.81 D) 14.809 E) 14.8 ---- -------- 16\. A cubic centimeter (cm^3^) is equivalent to what other metric volume unit? ---- ------------ A) milliliter B) liter C) deciliter D) centimeter E) millimeter ---- ------------ 17\. Which of the following describes a chemical property of gold? ---- --------------------------------------------------- A) Gold is a yellow metal. B) Gold is an inert (nonreactive) metal. C) Gold is a soft metal. D) Gold is a very dense metal. E) Gold is a good conductor of heat and electricity. ---- --------------------------------------------------- 18\. A homogeneous mixture is also called \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_. ---- -------------------------- A) a heterogeneous mixture. B) a pure substance. C) a compound. D) a solution. E) an element. ---- -------------------------- 19\. Titanium(IV) oxide has the formula ---- ----------- A) Ti~4~O B) TiO~4~ C) Ti(IV)O D) TiO~2~ E) Ti~4~O~2~ ---- ----------- 20\. What is the specific heat (J/g∙°C) of a metal object whose temperature increases by 3.0°C when 17.5 g of metal was heated with 38.5 J? A\) 4.18 B\) 0.15 C\) 0.73 D\) 1.4 E\) none of the above 21\. How much heat (kJ) is needed to raise the temperature of 100.0 grams of water from 25.0°C to 50.0°C? A\) 10450 B\) 0.598 C\) 1.05 D\) 10.5 E\) none of the above 22\. Which of the following is named **incorrectly**? A\) BaCl~2~; barium chloride B\) AlPO~4~; aluminum phosphate C\) NH~4~F; ammonium fluoride D\) FeSO~4~; iron(III) sulfate E\) All are correct. 23\) What is the correct formula for a potassium ion with 18 electrons? A\) P+ B) K+ C) K- D) P- E) none of the above 24\) How many electrons are in Br-? A\) 4 B) 7 C) 34 D) 36 E) none of the above 25\) How many protons and electrons are present in O2-? A\) 8 protons and 8 electrons B\) 10 protons and 8 electrons C\) 8 protons and 10 electrons D\) 16 protons and 8 electrons E\) none of the above