8. Quantities in Chemical Reactions
Thermochemical Equations
8. Quantities in Chemical Reactions
Thermochemical Equations
01:13
Practice this topic
- Multiple Choice
Nitromethane (CH3NO2), sometimes used as a fuel for drag racing, burns according to the following reaction:
4 CH3NO2 (l) + 7 O2 (g) → 4 CO2 (g) + 6 H2O (g) + 4 NO2 (g) ∆Hº = – 2441.6 kJ
How much heat is released by burning 125.0 g of nitromethane (MW:61.044 g/mol)?
- Multiple Choice
Consider the following reaction:
2 C6H6 (l) + 15 O2 (g) → 12 CO2 (g) + 6 H2O (g) ∆Hº = – 6278 kJ
What volume of benzene (C6H6, d = 0.880 g/mL, molar mass = 78.11 g/mol) is necessary to evolve 5.19 x 109 kJ of heat?
- Multiple Choice
The creation of liquid methanol is accomplished by the hydrogenation of carbon monoxide:
CO (g) + 2 H2 (g) → CH3OH (l) ∆Hº = – 128.1 kJ
How much heat (in kJ) is released when 125.0 g CO reacts with 2.32 x 102 g H2?
- Open QuestionThe following equation shows the conversion of aluminum oxide (from the ore bauxite) to aluminum:2 Al2O3(s) → 4 Al(s) + 3 O2(g) ∆H = +801 kcal/mol (+3350 kJ/mol)How many kilocalories are required to produce 10.0 g of aluminum? How many kilojoules?
- Open QuestionThe vaporization of Br2 from the liquid to the gas state requires 7.4 kcal/mol (31.0 kJ/mol).How many kilojoules are needed to evaporate 82 g of Br2?
- Open QuestionConverting liquid water to solid ice releases 1.44 kcal/mol (6.02 kJ/mol).How many kilocalories are released by freezing 32 g of H2O?
- Open QuestionGlucose, also known as 'blood sugar' when measured in blood, has the formula C6H12O6.What is the minimum amount of energy (in kJ) a plant must absorb to produce 15.0 g of glucose?