CART Thermochemistry and Energy 2

Question 1

Which calorimetry equation relates heat, mass, specific heat, and temperature change?

Accepted Answer

q = mcΔT

Answer

The equation q = mcΔT calculates heat by multiplying mass, specific heat capacity, and change in temperature.

Question 2

In a coffee-cup calorimeter experiment, the temperature of the solution rises after mixing two reactants. The reaction is:

Accepted Answer

Exothermic

Answer

A temperature rise in the calorimeter means the reaction released heat to the solution, indicating an exothermic reaction.

Question 3

The heat of combustion of propane (C₃H₈) is –2220 kJ/mol. How much heat is released by burning 0.5 mol of propane?

Accepted Answer

–1110 kJ

Answer

Multiplying 0.5 mol × (–2220 kJ/mol) = –1110 kJ, meaning 1110 kJ of heat is released.

Question 4

Which symbol represents the heat of a reaction measured at constant volume?

Accepted Answer

ΔU (or ΔE)

Answer

Internal energy change (ΔU or ΔE) represents heat flow at constant volume, as measured in a bomb calorimeter.

Question 5

Bond breaking in a chemical reaction requires ________ energy, while bond forming ________ energy.

Accepted Answer

absorbs; releases

Answer

Energy must be absorbed (input) to break bonds, and energy is released (output) when new bonds form.

CART - Chemistry Acceleration Readiness Test Practice Test