Heat of formation (∆Hr°) for CO2 is:
Correct answer: A. -394 kJ/mol
- A. -394 kJ/mol
- B. +394 kJ/mol
- C. -294 kJ/mol
- D. -390 kJ/mol
Explanation
Fact: The formation of CO2 from carbon and oxygen, is an exothermic reaction, meaning it releases heat. Therefore, it is negative and its value is -394 kJ/mol.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
Practise Thermochemistry and Energetics of Chemical Reactions
728 free Thermochemistry and Energetics of Chemical Reactions MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Thermochemistry and Energetics of Chemical Reactions questions
Enthalpy means
The heat liberated in the following reaction H+(ag) + OH- (aq) ➞ H2O(1) is:
The enthalpy change for the process C(s) ➝ C(g)corresponds to enthalpy of
No work is done at constant
H2 + O2 ➞ 2H2O ΔH = +285.5 kJ mol-1What will be the enthalpy change in the above reaction?
Combustion of graphite to form CO2 can be done in two ways. Reactions are given as follows: