Question

may absorb 11. Carbon monoxide rcacts with oxygen to form carbon dionide 2 CO(g)+ 0(g)2 COg) In a 1.00 L flask, 4.30 atm of CO reacts with 2.50 atm of O. Assuming that the temperature remains constant, what is the final pressure in the flask? a. 4.30 atm b. 6.80 atm 1.80 atm d. 4.65 atm 2.50 atm c. e. 12. A balloon is filled with He gas to a volume of 2.10 L at 35 °C. The baloon is placed in liquid nitrogen until its temperature reaches-196 "C. Assuming the pressure remains constart, what is the volume of the cooled balloon? a. 8.40 L b. 0.00909 L 0.525 L d. 0.375 L e. -0.375 L c. 13. Convert 618 mm Hg to kPa. (1 atm 760 mm Hg- 101.3 kPa) 4.64 x 10' kPa a. b. 1.23 kPa c. 0.813 kPa d. 0.0121 kPa 82.4 kPa е. 14. Iron oxide reacts with aluminum in an exothermic reaction. Fe;O,(s)+2 Al(s)-2 Fe(s) + Al O(s) The reaction of 5.00 g Fe O, with excess Al(s) evolves 26.6 kJ of energy in the form of heat. Calcula enthalpy change per mole of Fe Os reacted. a. -8.50 x 10 kJ/mol b. -5.32 kJ/mol c. -2.12 x 10 kJ/mol d. -2.12 x 10 kJ/mol e. -1.33 x 10 kJ/mol 15. How much energy (in kJ) is required to change the temperature of 325 g aluminum from 32 °C to The specific heat capacity of aluminum is 0.897 J/g-K. a. 228 kJ b. 238 kJ c. 2.16 kJ d. 284 kJ e. 46.3 kJ 16. Avogadro's hypothesis states that equal volumes of gases under the same conditions of tempe pressure have equal a. molar masses

Answer 1

11. 4.30 + 0.35 = 4.65 atm

12. using the Charles' law

2.10 / 305 = V / 77

Solving, V = 0.525 Liters

13. 760 mm Hg = 101.3 Kpa

618 / 760 * 101.3 = 82.37 KPa

14. Moles of Fe₂O₃= mass / molar mass = 5 / 160 = 0.0313 moles

Molar enthalpy = Enthalpy change / moles = -26.6 / 0.0313 = -8.5 * 10² KJ

15. Energy = mass * specific heat * temperature change = 325 * 0.897 * temeprature change