1. Calculate the work, w, done on the surroundings when a gas expands from 15L to 35L against a constantexternal pressure of 1.5 atm. [1 L . atm = 101 J](A) 5.3kJ (B) 3.0 kJ (C) +3.0 kJ (D) +5.3 kJ

2. A gas expands against a nonzero external pressure while in thermal isolation from the surroundings. For thisexpansion(A) E increases. (B) E does not change (C) E decreases (D) E = q

3. For a process at constant volume,(A) q = 0, w = 0, and E = 0 (B) w = 0 and E = q(C) w = 0 and H = q (D) w = 0 and E = H

4. For a process at constant pressure,(A) E = w and q = 0 (B) E = q and w = 0 (C) E = H (D) H = q

5. Most chemical reactions are carried out in one of two ways:I. In an open vessel at constant atmospheric pressureII. In a closed vesselWhich is true ?(A)H = q for condition I and E = q for condition II(B) E = q for condition I and H = q for condition II(C) H = w for condition I and E = w for condition II(D) E = w for condition I and H = w condition II

6. For a particular process that is carried out at constant pressure, q = 125 kJ and w = 15 kJ. Therefore,(A) E = 110 kJ and H = 125 kJ (B) E = 125 kJ and H = 110 kJ(C) E = 125 kJ and H = 140 kJ (D) E = 140 kJ and H = 125 kJ

7. A process is carried out at constant pressure. Given that E is positive and H is negative,(A) The system absorbs heat and expands during the process.(B) The system absorbs heat and contracts during the process.(C) The system loses heat and expands during the process.(D) The system loses heat and contracts during the process.

8. For which of the reactions shown below should H be larger than E ?I. 2SO2(g) + O2(g) 2SO3(g)II. C3H8(g) + 5O2(g) 3CO2(g) + 4H2O()III. H2(g) + Cl2(g) 2HCl(g)IV. N2O4(g) 2NO2(g)(A) I (B) III (C) IV (D) II and IV

9. How much heat is absorbed/released when 20.00g of NH3(g) reacts in the presence of excess O2(g) to produceNO(g) and H2O() according to the following chemical equation ?4NH3(g) + 5O2(g) 4NO(g) + 6H2O() H = +1168 kJ(A) 342.9 kJ of heat are absorbed. (B) 342.9 kJ of heat are released.(C) 1372 kJ of heat are absorbed. (D) 1372 kJ of heat are released.

UNIT- THERMODYNAMICS RACE-1

10. Coal gasification can be represented by the equation :2C(s) + 2H2O(g) CH4(g) + CO2(g) H = ?

Use the following information to find H for the reaction above.CO(g) + H2(g) C(s) + H2O(g) H = 131 kJCO(g) + H2O(g) CO2(g) + H2(g) H = 41 kJCO(g) + 3H2(g) CH4(g) + H2O(g) H = 206 kJ

(A) 15 kJ (B) 116 kJ (C) 116 kJ (D) 372 kJ

11. For which should the standard heat of formation Hf, be zero at 25C ?(A) O(g) (B) O2(g) (C) O3(g) (D) All the above

12. The values of Hf for the three states of benzene are approximately 22 kcal/mol, 11 kcal/mol, and 20 kcal/mol. Which is the value for solid benzene ?(A) 22 kcal/mol (B) 11 kcal/mol(C) 20 kcal/mol (D) Cannot be determined without additional information

13. Ethyl alcohol is produced by the fermentation of glucose, C6H12O6.C6H12O6() 2C2H5OH() + 2CO2(g)H = 82 kJ

Given that the enthalpy of formation is 277.7 kJ/mol for C2H5OH() and 393.5 kJ/mol for CO2(g), find theenthalpy of formation for C6H12O6.(A) 1424 kJ/mol (B) 1260 kJ/mol (C) 753 kJ/mol (D) 671 kJ/mol

14. The combustion of 0.100 g of ethene causes a temperature rise of 2.00C in a bomb calorimeter that has a heatcapacity of 2.510 kJ/C. What is the internal energy change per mole of ethene for the combustion? Ethene =C2H4(g).(A) 1410 kJ/mol (B) 5.02 kJ/mol (C) 251 kJ/mol (D) +251 kJ/mol

15. H for the reaction, SiH4(g) + 2O2(g) SiO2(s) + 2H2O(), is 1517 kJ. What would be the value of H if thewater formed is in the gaseous state ? H for H2O() H2O(g) is + 44.0 kJ/mole.(A) 1561 kJ (B) 1517 kJ (C) 1473 kJ (D) 1429 kJ

ANSWER KEY

Que. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Ans. B C B D A A D C A A B A B A D