Unit 5: Multiple Choice

Transcription

1 Unit 5: Multiple Choice MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The ΔE of a system that releases 12.4 J of heat and does 4.2 J of work on the surroundings is J. A) B) 16.6 C) 12.4 D) -8.2 E) 4.2 1) 2) The temperature of a 15-g sample of lead metal increases from 22 C to 37 C upon the addition of 29.0 J of heat. The specific heat capacity of the lead is J/g-K. A) -29 B) 7.8 C)29 D) 1.9 E) ) 3) The specific heat of bromine liquid is J/g K. The molar heat capacity (in J/mol-K) of bromine liquid is. A) 18.1 B) 707 C) 9.05 D) E) ) 4) The specific heat of liquid bromine is J/g-K. How much heat (J) is required to raise the temperature of 10.0 ml of bromine from C to C? The density of liquid bromine: 3.12 g/ml. A) 10.4 B) 32.4 C) 16.2 D) 300 E) ) 5) The ΔH for the solution process when solid sodium hydroxide dissolves in water is 44.4 kj/mol. When a 13.9-g sample of NaOH dissolves in g of water in a coffee-cup calorimeter, the temperature increases from 23.0 C to C. Assume that the solution has the same specific heat as liquid water, i.e., 4.18 J/g-K. A) 37.0 C B) 35.2 C C) 24.0 C D) 37.8 C E) 40.2 C 5) 6) Calculate the value of ΔE in joules for a system that loses 50 J of heat and has 150 J of work performed on it by the surroundings. A) -200 B) 50 C) +200 D) 100 E) ) 7) The change in the internal energy of a system that absorbs 2,500 J of heat and that does 7,655 J of work on the surroundings is J. A) -5,155 B) 10,155 C) D) 5,155 E) -10,155 7) 8) The value of ΔH for the reaction below is -126 kj. kj are released when 2.00 mol of NaOH is formed in the reaction? 8) 2Na2O2 (s) + 2H2O (l) 4NaOH (s) + O2 (g) A) 7.8 B) 252 C) -126 D) 63 E) 3.9 9) The value of ΔH for the reaction below is -126 kj. The amount of heat that is released by the reaction of 25.0 g of Na2O2 with water 9) 2Na2O2 (s) + 2H2O (l) 4NaOH (s) + O2 (g) A) 80.8 B) 40.4 C) -126 D) 20.2 E)

2 10) The value of ΔH for the reaction below is -186 kj. Calculate the heat (kj) released from the reaction of 25 g of Cl2. 10) H2 (g) + Cl2 (g) 2HCl (g) A) 33 B) -186 C) D) 66 E) 47 11) The enthalpy change for the following reaction is kj: 11) 2H2 (g) + O2 (g) 2H2O (g) Therefore, the enthalpy change for the following reaction is kj: 4H2 (g) + 2O2 (g) 4H2O (g) A) B) C) D) E) ) The value of ΔH for the reaction below is kj: 12) CH3OH (l) CO (g) + 2H2 (g) How many kj of heat are consumed when 15.5 g of CH3OH (l) decomposes as shown in the equation? A) 0.48 B) 62.0 C)32 D) 8.3 E) ) The value of ΔH for the reaction below is kj: 13) CH3OH (l) CO (g) + 2H2 (g) How many kj of heat are consumed when 5.10 g of H2 (g) is formed as shown in the equation? A) 128 B) 326 C) 62.0 D) 653 E) ) The value of ΔH for the reaction below is kj: 14) 2Ba (s) + O2 (g) 2BaO (s) How many kj of heat are released when 5.75 g of BaO (s) is produced? A) 23.2 B) 56.9 C) 20.8 D) 193 E)

3 15) ΔH for the reaction 15) IF5 (g) IF3 (g) + F2 (g) is kj, give the data below. IF (g) + F2 (g) IF3 (g) IF (g) + 2 F2 (g) IF5 (g) ΔH = -390 kj ΔH = -745 kj A) B) +355 C) -35 D) +35 E) ) Given the following reactions 16) Fe2O3 (s) + 3CO (s) 2Fe (s) + 3CO2 (g) 3Fe (s) + 4CO2 (s) 4CO (g) + Fe3O4 (s) H = kj H = kj the enthalpy of the reaction of Fe2O3 with CO 3Fe2O3 (s) + CO (g) CO2 (g) + 2Fe3O4 (s) A) B) C) 40.5 D) +109 E) ) Given the following reactions 17) N2 (g) + 2O2 (g) 2NO2 (g) 2NO (g) + O2 (g) 2NO2 (g) ΔH = 66.4 kj ΔH = kj the enthalpy of the reaction of the nitrogen to produce nitric oxide N2 (g) + O2 (g) 2NO (g) A) B) 90.3 C) D) E) ) Given the following reactions 18) (1) 2NO N2 + O2 ΔH = -180 kj (2) 2NO + O2 2NO2 ΔH = -112 kj the enthalpy of the reaction of nitrogen with oxygen to produce nitrogen dioxide N2 + 2O2 2NO2 A) -292 B) 292 C) -146 D) 68 E) -68 3

4 19) Given the following reactions: 19) 2S (s) + 3O2 (g) 2SO3 (g) S (s) + O2 (g) SO2 (g) H = -790 kj H = -297 kj the enthalpy of the reaction in which sulfur dioxide is oxidized to sulfur trioxide 2SO2 (g) + O2 (g) 2SO3 (g) A) -543 B) 196 C) 1087 D) E) ) Given the following reactions 20) CaCO3 (s) CaO (s) + CO2 (g) C (s, graphite) + O2 (g) CO2 (g) ΔH = kj ΔH = kj the enthalpy of the reaction CaCO3 (s) CaO (s) + C (s, graphite) + O2 (g) A) B) C) D) E) ) Given the following reactions 21) N2 (g) + O2 (g) 2NO (g) 2NO( g) + O2 (g) 2NO2 (g) ΔH = kj ΔH = kj the enthalpy for the decomposition of nitrogen dioxide into molecular nitrogen and oxygen 2NO2 (g) N2 (g) + 2O2 (g) A) 45.5 B) C) D) E)

5 22) Given the data in the table below, ΔH rxn for the reaction 22) Ca(OH)2 + 2H3AsO4 Ca(H2AsO4)2 + 2H2O Ca(OH) H3AsO Ca(H2AsO4) H2O A) B) C) D) E) ) Given the data in the table below, ΔH rxn for the reaction 23) 4NH3 (g) + 5O2 (g) 4NO (g) + 6H2O (l) H2O (l) -286 NO (g) 90 NO2 (g) 34 HNO3 (aq) -207 NH3 (g) -46 A) B) -150 C) D) E) The ΔHf of O2 (g) is needed for the calculation. 5

6 24) Given the data in the table below, ΔH rxn for the reaction 24) C2H5OH (l) + O2 (g) CH3CO2H (l) + H2O (l) C2H4 (g) 52.3 C2H5OH (l) CH3CO2H (l) H2O (l) A) B) C) D) E) The value of ΔHf of O2 (g) is required for the calculation. 25) Given the data in the table below, ΔH rxn for the reaction 25) 3NO2 (g) + H2O (l) 2HNO3 (aq) + NO (g) H2O (l) -286 NO (g) 90 NO2 (g) 34 HNO3 (aq) -207 NH3 (g) -46 A) 140 B) -64 C) -508 D) 64 E)

7 26) Given the data in the table below and ΔH rxn for the reaction 26) SO2Cl2 (g) + 2H2O (l) H2SO4 (l) + 2HCl (g) ΔH = -62 kj ΔH f of HCl (g) is kj/mol. SO2 (g) -297 SO3 (g) -396 SO2Cl2 (g) -364 H2SO4 (l) -814 H2O (l) -286 A) -184 B) 60 C)30 D) -92 E) Insufficient data are given. 7

8 Answer Key Testname: CH5_MC 1) A 2) E 3) E 4) C 5) A 6) D 7) A 8) D 9) D 10) D 11) A 12) B 13) E 14) C 15) B 16) A 17) A 18) D 19) E 20) A 21) B 22) C 23) C 24) A 25) E 26) D 8