8. Thermochemistry
Thermochemical Equations
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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)?
5064views8rank1comments - 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?
3490views5rank - 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?
5497views10rank1comments - Multiple ChoiceConsider two identical iron nails: One nail is heated to 95℃, the other is cooled to 15℃. The two nails are placed in a coffee cup calorimeter and the system is allowed to come to thermal equilibrium. What is the final temperature of the two nails?854views
- Textbook QuestionIsooctane is the primary component of gasoline and burns in air to produce water rand carbon dioxide2 C8H18(g) + 25 O2(g) → 16 CO2(g) + 18 H2O(l) ΔH°= —10,940 kJHow much energy is released if 100.0 mL of isooctane (density = 0.690 g/mL) are burned(a) 3300 kJ(b) 6620 kJ(c) 6950 kJ(d) 3.02 kJ2214views
- Textbook Question
Consider the following reaction: 2 CH3OH(g) → 2 CH4(g) + O2(g) ΔH = +252.8 kJ (d) How many kilojoules of heat are released when 38.5 g of CH4(g) reacts completely with O2(g) to form CH3OH(g) at constant pressure?
458views - Textbook Question
Consider the following reaction: 2 CH3OH(g) → 2 CH4(g) + O2(g) ΔH = +252.8 kJ (b) Calculate the amount of heat transferred when 24.0 g of CH3OH(g) is decomposed by this reaction at constant pressure.
718views1rank - Textbook Question
When solutions containing silver ions and chloride ions are mixed, silver chloride precipitates Ag+(aq) + Cl-(aq) → AgCl(s) H = -65.5 kJ (a) Calculate H for the production of 0.450 mol of AgCl by this reaction. (b) Calculate H for the production of 9.00 g of AgCl. (c) Calculate H when 9.25⨉10-4 mol of AgCl dissolves in water.
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