General, Organic & Biological Chemistry, 5e (Timberlake) Chapter Chemical Reactions and Quantities 7.1 Multiple-Choice Questions 1) A chemical equation is balanced when A) the total number of molecules is the same in reactants and products B) the total number of ions is the same in reactants and products C) the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products D) the number of atoms of each element is the same in reactants and products E) the charge on each atom is the same in reactants and products Answer: D Objective: 7.1 Global Outcomes: GO2 2) In any balanced chemical equation, the number of each type of atom on both sides of the equation is A) doubled B) the same C) decreased by one D) increased by one E) dependent on the temperature Answer: B Objective: 7.1 Global Outcomes: GO2 3) Which of the following gives the balanced equation for this reaction? K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3 A) KPO4 + CaNO3 + KNO3 B) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 3KNO3 C) 2K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 6KNO3 D) 2K3PO4 + 3Ca(NO3)2 → Ca3(PO4)2 + 6KNO3 E) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3 Answer: D Objective: 7.1 Global Outcomes: GO2 Copyright © 2016 Pearson Education, Inc 4) Which of the following correctly gives the best coefficients for the reaction below? N2H4 + H2O2 → N2 + H2O A) 1, 1, ,1 B) 1, 2, 1, C) 2, 4, 2, D) 1, 4, 1, E) 2, 4, 2, Answer: B Objective: 7.1 Global Outcomes: GO2 5) What coefficient is placed in front of O2 to complete the balancing of the following equation? C5H8 + ? O2 → 5CO2 + 4H2O A) B) C) D) E) Answer: D Objective: 7.1 Global Outcomes: GO2 6) What is the coefficient of hydrogen, H2, when the following equation is balanced? Al + H2SO4 → Al2(SO4)3 + ? H2 A) B) C) D) E) Answer: C Objective: 7.1 Global Outcomes: GO2 Copyright © 2016 Pearson Education, Inc 7) In this reaction, what is the coefficient for calcium oxide? CaO(s) + CO2(g) → CaCO3(s) A) B) C) D) E) Answer: A Objective: 7.1 Global Outcomes: GO2 8) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for sodium chloride? Pb(NO3)2(aq) + NaCl(aq) → PbCl2(s) + NaNO3(aq) A) B) C) D) E) Answer: B Objective: 7.1 Global Outcomes: GO2 9) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for H2? Fe(s) + HCl(aq) → FeCl3(aq) + H2(g) A) B) C) D) E) Answer: C Objective: 7.1 Global Outcomes: GO2 Copyright © 2016 Pearson Education, Inc 10) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for aluminum chloride? Al(s) + Cl2(g) → AlCl3(s) A) B) C) D) E) Answer: B Objective: 7.1 Global Outcomes: GO2 Pentane (C5H12) reacts with oxygen (O2) to form carbon dioxide (CO2) and water (H2O) according to the following reaction Answer the question(s) that follow about this reaction C5H12 + ? O2 → ? CO2 + ? H2O 11) What is the coefficient for oxygen in the balanced equation? A) B) C) D) E) Answer: E Objective: 7.1 Global Outcomes: GO2 12) What is the coefficient for carbon dioxide in the balanced equation? A) B) C) D) E) Answer: C Objective: 7.1 Global Outcomes: GO2 13) What is the coefficient for water in the balanced equation? A) B) C) D) E) Answer: D Objective: 7.1 Global Outcomes: GO2 14) In a reaction, two or more elements or compounds form one product A) decomposition B) single replacement C) dehydration D) double replacement E) combination Answer: E Copyright © 2016 Pearson Education, Inc Objective: 7.2 Global Outcomes: GO2 15) The following reaction takes place when an electric current is passed through water It is an example of a reaction 2H2O → 2H2 + O2 A) combination B) single replacement C) dehydration D) decomposition E) double replacement Answer: D Objective: 7.2 Global Outcomes: GO2 16) What is the classification for this reaction? SO3 (g) + H2O (l) → H2SO4(l) A) decomposition B) combination C) replacement D) double replacement E) oxidation reduction Answer: B Objective: 7.2 Global Outcomes: GO2 Copyright © 2016 Pearson Education, Inc ... Objective: 7. 1 Global Outcomes: GO2 5) What coefficient is placed in front of O2 to complete the balancing of the following equation? C5H8 + ? O2 → 5CO2 + 4H2O A) B) C) D) E) Answer: D Objective: 7. 1... + H2SO4 → Al2(SO4)3 + ? H2 A) B) C) D) E) Answer: C Objective: 7. 1 Global Outcomes: GO2 Copyright © 2016 Pearson Education, Inc 7) In this reaction, what is the coefficient for calcium oxide?... C) D) E) Answer: E Objective: 7. 1 Global Outcomes: GO2 12) What is the coefficient for carbon dioxide in the balanced equation? A) B) C) D) E) Answer: C Objective: 7. 1 Global Outcomes: GO2 13)