Thermochemistry Practice
8 problems · instant feedback · full explanations
Thermochemistry quantifies heat flow and predicts spontaneity. These eight problems cover calorimetry calculations, Hess's law, and the meanings of enthalpy, entropy, and Gibbs free energy.
Q1.
How much heat is needed to raise the temperature of 100 g of water by 10.0 C? Use c = 4.184 J/g C.
Numerical answer (J) · Easy
Q2.
For an exothermic reaction, the sign of deltaH is:
Multiple choice · Beginner
Q3.
In an endothermic process, the system absorbs heat from the surroundings.
True / False · Beginner
Q4.
Hess's law states that the total enthalpy change of a reaction:
Multiple choice · Easy
Q5.
Use standard enthalpies of formation (kJ/mol): CH4(g) -74.8, O2(g) 0, CO2(g) -393.5, H2O(l) -285.8. Find deltaH for CH4 + 2O2 -> CO2 + 2H2O.
Numerical answer (kJ/mol) · Hard
Q6.
Enthalpy change for a chemical reaction is commonly reported in units of:
Multiple choice · Easy
Q7.
The entropy of the universe increases in every spontaneous process.
True / False · Medium
Q8.
A reaction with a negative deltaG is:
Multiple choice · Easy