Question

10. Given the thermochemical data below, what is the change in enthalpy when 10.0 g of H, are reacted? N; (g) + 3H2(g) → 2NH, (g): AH = -91.2 kJ (A) -452 kJ (B) +452 kJ (C) -151 kJ (D) -1357 kJ 11. Which of the following is NOT a state function? 1. Heat 2. Change in enthalpy 3. Change in internal energy 4. Change in pressure (A) 1 only (B) 2 only (C) 2 and 3 (D) 1 and 3 (E) 3 and 4 12. Which of the following reactions when run at constant pressure will have a positive value for work? (A) CH4 (g) +20; (g) → 2H20 (1) + CO2(g) (B) (NH),CO (aq) + H20 (1) 2NH, (aq) + CO2(g) (C) Hz (g) + Cl (8) ► 2HCl (g) (D) 2HgO (3) ► 2Hg (1) + O2(g) (E) Both A and C 13. The sign of AH for the process CO2 (s) + CO2(g) is (A) negative, and the reaction is endothermic. (B) positive, and the reaction is exothermic. (C) positive, and the reaction is endothermic. (D) negative, and the reaction is exothermic. (E) impossible to predict because AHP for CO2 (s) and AH? for CO2 (g) are not given. 14. Consider the following specific heat of metals. Metal Specific Heat (J/g:"C) copper 0.385 cobalt 0.418 chromium 0.447 gold 0.129 silver 0.237 If the same amount of heat is added to 100 g samples of each of the metals, which are all at the same temperature, which metal will reach the highest temperature? (A) Copper (B) Cobalt (C) Chromium (D) Gold (E) Silver 15. When calcium chloride is dissolved in water in a process that is thermally insulated from the surroundings, the temperature is observed to rise from room temperature to above 100°C. The rise in temperature is due to the energy... (A) absorbed in dissolving and hydrating the solid CaCl2. (B) evolved in dissolving and hydrating the solid CaCl2. (C) evolved from the surroundings to the solution. (D) absorbed from the solution into the surroundings. 16. Which of the following has a standard heat of formation of zero at 25°C and 1.0 atm? (A) 026) (B) H20 (1) (C) Fe (1) (D) 02 (8)