Chapter 9 Test
What is the study of the mass relationships of elements in compounds? a percentage yield b Avogadro's principle c composition stoichiometry d reaction stoichiometry
composition stoichiometry
A determination of the masses and number of moles of sulfur and oxygen in the compound sulfur dioxide would be studied in a chemical equilibrium. b composition stoichiometry. c chemical kinetics. d reaction stoichiometry.
composition stoichiometry.
The units of molar mass are a mol/g. b amu/g. c amu/mol. d g/mol.
mol/g.
If one knows the mass and molar mass of reactant A and the molar mass of product D in a chemical reaction, one can determine the mass of product D produced by using the a mole ratio of D to A from the chemical equation. b group numbers of the elements of A and D in the periodic table. c electron configurations of the atoms in A and D. d estimated bond energies involved in the reaction.
mole ratio of D to A from the chemical equation.
A balanced chemical equation allows one to determine the a mole ratio of any two substances in the reaction. b energy released in the reaction. c mechanism involved in the reaction. d electron configuration of all elements in the reaction.
mole ratio of any two substances in the reaction.
Each of the four types of reaction stoichiometry problems requires using a a chart of electron configurations. b table of bond energies. c Lewis structure. d mole ratio.
mole ratio.
A chemical equation is balanced when the a coefficients of the reactants equal the coefficients of the products. b products and reactants are the same chemicals. c subscripts of the reactants equal the subscripts of the products. d same number of each kind of atom appears in the reactants and in the products.
same number of each kind of atom appears in the reactants and in the products.
Which branch of chemistry deals with the mass relationships of elements in compounds and the mass relationships among reactants and products in chemical reactions? a stoichiometry b entropy c qualitative analysis d chemical kinetics
stoichiometry
Which of the following would not be studied in the branch of chemistry called stoichiometry? a the number of moles of hydrogen that reacts completely with a known quantity of oxygen b the amount of energy required to break the ionic bonds in calcium fluoride c the mass of carbon produced when a known mass of sucrose decomposes d the mole ratio of aluminum and chlorine in aluminum chloride
the amount of energy required to break the ionic bonds in calcium fluoride
In the chemical equation wA + xB → yC + zD, if one knows the mass of A and the molar masses of A, B, C, and D, one can determine a the mass of any of the reactants or products. b the mass of B only. c the total mass of C and D only. d the total mass of A and B only.
the mass of any of the reactants or products.
Which of the following would be investigated in reaction stoichiometry? a the mass of potassium required to produce a known mass of potassium chloride b the amount of energy released in chemical reactions c the types of bonds that break and form when acids react with metals d the masses of hydrogen and oxygen in water
the mass of potassium required to produce a known mass of potassium chloride
For the reaction represented by the equation C + 2H2→ CH4, how many moles of hydrogen are required to produce 10 mol of methane, CH4? (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 20 mol b 10 mol c 2 mol d 4 mol
20 mol
For the reaction represented by the equation SO3 + H2O → H2SO4, how many grams of sulfuric acid can be produced from 200. g of sulfur trioxide and 100. g of water? a 200. g b 245 g c 285 g d 100. g
245 g
In the reaction represented by the equation C + 2H2→ CH4, what is the mole ratio of hydrogen to methane? a 1:2 b 2:4 c 2:1 d 1:1
2:1
In the reaction represented by the equation C + 2H2→ CH4, what is the mole ratio of hydrogen to methane? a 2:4 b 1:1 c 1:2 d 2:1
2:1
Which equation is not balanced? a 2H2 + O2 -> 2H2O b 2H2 + O2 + H2O c 4H2 + 2O2 -> 4H2O d H2 + H2 + O2 -> H2O + H2O
2H2 + O2 + H2O
The Haber process for producing ammonia commercially is represented by the equation N2(g) + 3H2(g) → 2NH3(g). To completely convert 9.0 mol hydrogen gas to ammonia gas, how many moles of nitrogen gas are required? a 2.0 mol b 6.0 mol c 3.0 mol d 1.0 mol
3.0 mol
In the equation 2KClO3→ 2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely? (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 1.0 mol b 2.5 mol c 4.5 mol d 3.0 mol
4.5 mol
In the decomposition of hydrogen peroxide, the percentage yield of oxygen is 93.0%. What is the actual yield in grams of oxygen if you start with 100. g of H2O2? The reaction proceeds according to the equation 2H2O2(l) -> 2H2O(l) + O2(g). (Show your work on a separate sheet of paper and keep it to turn in when you return to school)
43.8g O2
In the reaction represented by the equation 2Al2O3→ 4Al + 3O2, what is the mole ratio of aluminum to oxygen? a 2:3 b 10:6 c 4:3 d 3:4
4:3
In the reaction represented by the equation 2Al2O3→ 4Al + 3O2, what is the mole ratio of aluminum to oxygen? a 4:3 b 2:3 c 3:4 d 10:6
4:3
For the reaction represented by the equation 2KlO3→ 2KCl + 3O2, how many moles of potassium chlorate are required to produce 250. g of oxygen? a 4.97 mol b 4.32 mol c 2.00 mol d 5.21 mol
5.21 mol
In the reaction represented by the equation 2NH3 + CO2 CO(NH2)2 + H20, 30.7 g of CO(NH2)2 forms per 1.00 mol of CO2 that reacts when NH3 is in excess. What is the percentage yield? (Show your work on a separate sheet of paper and keep it to turn in when you return to school)
51.1%
For the reaction represented by the equation 2Fe + O2→ 2FeO, how many grams of iron(II) oxide are produced from 8.00 mol of iron in an excess of oxygen? a 71.8 g b 575 g c 1310 g d 712 g
575 g
For the reaction represented by the equation N2 + 3H2→ 2NH3, how many moles of nitrogen are required to produce 18 mol of ammonia? (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 9.0 mol b 36 mol c 18 mol d 27 mol
9.0 mol
For the reaction represented by the equation Cl2 + 2KBr → 2KCl + Br2, calculate the percentage yield if 200. g of chlorine react with excess potassium bromide to produce 410. g of bromine. (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 91.0% b 82.1% c 73.4% d 98.9%
91.0%
For the reaction represented by the equation SO3 + H2O → H2SO4, calculate the percentage yield if 500. g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid. (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 82.7% b 91.2% c 88.3% d 93.9%
93.9%
For the reaction represented by the equation Pb(NO3)2 + 2KI → PbI2 + 2KNO3, how many moles of lead(II) iodide are produced from 300. g of potassium iodide and an excess of Pb(NO3)2? a 11.0 mol b 1.81 mol c 3.61 mol d 0.904 mol
0.904 mol
Given the equation , the starting mass of A, and its molar mass, and you are asked to determine the moles of C produced, your first step in solving the problem is the multiply the given mass of A by a 1 mol A / molar mass A b 2 mol C / 3 mol A c molar mass A / 1 mol A d 3 mol A / 2 mol C
1 mol A / molar mass A
Which coefficients correctly balance the formula mc013-1.jpg? a 1,2,2 b 1,1,2 c 2,2,2 d 2,1,1
1,1,2
For the reaction represented by the equation Cl2 + 2KBr → 2KCl + Br2, how many moles of potassium chloride are produced from 119 g of potassium bromide? a 0.236 mol b 0.119 mol c 0.581 mol d 1.00 mol
1.00 mol
For the reaction represented by the equation 2H2 + O2→ 2H2O, how many grams of water are produced from 6.00 mol of hydrogen? a 2.00 g b 108 g c 54.0 g d 6.00 g
108 g
For the reaction represented by the equation 2H2 + O2→ 2H2O, how many moles of water can be produced from 6.0 mol of oxygen? a 18 mol b 12 mol c 6.0 mol d 2.0 mol
12 mol
In the reaction represented by the equation N2 + 3H2→ 2NH3, what is the mole ratio of nitrogen to ammonia? a 1:2 b 2:3 c 1:1 d 1:3
1:2
In the reaction represented by the equation N2 + 3H2→ 2NH3, what is the mole ratio of nitrogen to ammonia? a 2:3 b 1:3 c 1:1 d 1:2
1:2
Ozone, O3, is produced by the reaction represented by the following equation:What mass of ozone will form from the reaction of 2.0 g of NO2 in a car's exhaust and excess oxygen? a 1.8 g O3 b 2.1 g O3 c 4.2 g O3 d 1.1 g O3
2.1 g O3
For the reaction represented by the equation 3Fe + 4H2O → Fe3O4 + 4H2, how many moles of iron(III) oxide are produced from 500. g of iron in an excess of H2O? a 12.98 mol b 8.95 mol c 2.98 mol d 1.04 mol
2.98 mol
For the reaction represented by the equation C + 2H2→ CH4, how many moles of hydrogen are required to produce 10 mol of methane, CH4? a 10 mol b 2 mol c 20 mol d 4 mol
20 mol
The Haber process for producing ammonia commercially is represented by the equation N2(g) + 3H2(g) → 2NH3(g). To completely convert 9.0 mol hydrogen gas to ammonia gas, how many moles of nitrogen gas are required? (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 2.0 mol b 3.0 mol c 1.0 mol d 6.0 mol
3.0 mol
For the reaction represented by the equation SO3 + H2O → H2SO4, how many grams of sulfur trioxide are required to produce 4.00 mol of sulfuric acid in an excess of water? a 160. g b 320. g c 80.0 g d 240. g
320. g
In the reaction represented by the equation N2 + 3H2→ 2NH3, what is the mole ratio of hydrogen to ammonia? a 1:1 b 6:8 c 2:1 d 3:2
3:2
In the reaction represented by the equation N2 + 3H2→ 2NH3, what is the mole ratio of hydrogen to ammonia? a 1:1 b 6:8 c 3:2 d 2:1
3:2
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of hydrogen are produced if 120. g of sodium and 80. g of water are available? a 200 g b 4.5 g c 80. g d 45 g
4.5 g
In the equation 2KClO3→ 2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely? a 2.5 mol b 3.0 mol c 4.5 mol d 1.0 mol
4.5 mol
For the reaction represented by the equation 2HNO3 + Mg(OH)2→ Mg(NO3)2 + 2H2O, how many grams of magnesium nitrate are produced from 8.00 mol of nitric acid, HNO3, and an excess of Mg(OH)2? a 593 g b 445 g c 818 g d 148 g
593 g
For the reaction represented by the equation CH4 + 2O2→ CO2 + 2H2O, how many moles of carbon dioxide are produced from the combustion of 100. g of methane? a 6.23 mol b 12.5 mol c 25 mol d 10.8 mol
6.23 mol
For the reaction represented by the equation 2Na + Cl2→ 2NaCl, how many grams of chlorine gas are required to react completely with 2.00 mol of sodium? a 35.5 g b 70.9 g c 212.7 g d 141.8 g
70.9 g
For the reaction represented by the equation CH4 + 2O2→ 2H2O + CO2, calculate the percentage yield of carbon dioxide if 1000. g of methane react with excess oxygen to produce 2300. g of carbon dioxide. (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 83.88% b 92.76% c 89.14% d 96.78%
83.88%
For the reaction represented by the equation Mg + 2HCl → H2 + MgCl2, calculate the percentage yield of magnesium chloride if 100. g of magnesium react with excess hydrochloric acid to yield 330. g of magnesium chloride. (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 74.3% b 81.6% c 84.2% d 71.8%
84.2%
When the formula equation is correctly balanced the coefficient of Fe is number a 9. b 7. c 3. d 2.
9.
For the reaction represented by the equation N2 + 3H2→ 2NH3, how many moles of nitrogen are required to produce 18 mol of ammonia? a 9.0 mol b 27 mol c 36 mol d 18 mol
9.0 mol
What is the measured amount of a product obtained from a chemical reaction? a percentage yield b actual yield c theoretical yield d mole ratio
actual yield
If one knows the mole ratio of a reactant and product in a chemical reaction, one can a calculate the mass of the product produced from a known mass of reactant. b decide whether the reaction is reversible. c estimate the energy released in the reaction. d calculate the speed of the reaction.
calculate the mass of the product produced from a known mass of reactant.
To balance a chemical equation, it may be necessary to adjust the a subscripts. b formulas of the products. c coefficients. d number of products.
coefficients.
The units of molar mass are a g/mol. b amu/mol. c mol/g. d amu/g.
g/mol
In most chemical reactions the amount of product obtained is a less than the theoretical yield. b equal to the theoretical yield. c more than the theoretical yield. d more than the percentage yield.
less than the theoretical yield.
In the chemical reaction represented by the equation wA + xB → yC + zD, a comparison of the number of moles of A to the number of moles of C would be a(n) a mole ratio. b energy proportion. c mass ratio. d electron ratio.
mole ratio
If one knows the mass and molar mass of reactant A and the molar mass of product D in a chemical reaction, one can determine the mass of product D produced by using the a estimated bond energies involved in the reaction. b mole ratio of D to A from the chemical equation. c electron configurations of the atoms in A and D. d group numbers of the elements of A and D in the periodic table.
mole ratio of D to A from the chemical equation.
What is the ratio of the actual yield to the theoretical yield, multiplied by 100%? a excess yield b percentage yield c Avogadro yield d mole ratio
percentage yield
A chemist interested in the efficiency of a chemical reaction would calculate the a mole ratio. b rate of reaction. c percentage yield. d energy released.
percentage yield.
What is the study of the mass relationships among reactants and products in a chemical reaction? a periodic law b electron configuration c reaction stoichiometry d composition stoichiometry
reaction stoichiometry
The coefficients in a chemical equation represent the a relative numbers of moles of reactants and products. b number of valence electrons involved in the reaction. c masses, in grams, of all reactants and products. d number of atoms in each compound in a reaction.
relative numbers of moles of reactants and products.
In what kind of reaction do two or more substances combine to form a new compound? a combustion reaction b decomposition reaction c synthesis reaction d double-displacement reaction
synthesis reaction
If the percentage yield is equal to 100%, then a the actual yield is less than the theoretical yield. b there was no limiting reactant. c the actual yield is equal to the theoretical yield. d the actual yield is greater than the theoretical yield.
the actual yield is equal to the theoretical yield.
What is the maximum possible amount of product obtained in a chemical reaction? a mole ratio b percentage yield c actual yield d theoretical yield
theoretical yield
For the reaction represented by the equation 2H2 + O2→ 2H2O, how many moles of water can be produced from 6.0 mol of oxygen? (Show your work on a separate sheet of paper and keep it to turn in when you return to school) a 12 mol b 6.0 mol c 2.0 mol d 18 mol
12 mol
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of sodium hydroxide are produced from 3.0 mol of sodium with an excess of water? a 80. g b 240 g c 120 g d 40. g
120 g
For the reaction represented by the equation Cl2 + 2KBr → 2KCl + Br2, how many grams of potassium chloride can be produced from 300. g each of chlorine and potassium bromide? a 188 g b 111 g c 98.7 g d 451 g
188 g
