Question

20 g of NaCl is poured into a coffee cup calorimeter containing 250 mL of water. If the temperature inside the calorimeter drops 1°C by the time, the NaCl is totally dissolved, what is the heat of solution for NaCl and water? (specific heat of water is 4.18 J/g°C)

• A. -3 kJ/mol
• B. -1 kJ/mol
• C. 1 kJ/mol
• D. 3 kJ/mol

Hint:

To calculate the heat of solution, use the formula Q = mcΔT and remember to convert the units of mass and temperature properly.

Answer 1

The Correct Option is D

The heat change can be calculated using the formula: \[ Q = mc\Delta T \] Where m is the mass of water, c is the specific heat of water, and $\Delta T$ is the change in temperature. For the NaCl, the heat change corresponds to its heat of solution.