Question

A student mixes two aqueous solutions, whose masses are 30.0 g and 35.0 g, together. Each solution is initially at a temperature of 25.0°C. Upon mixing the solutions, a chemical reaction occurs. The final solution has a temperature of 30.0°C. What is the heat change, in kJ, for this reaction?
a) 5.25 kJ
b) 1360 kJ
c) 1.36 kJ
d) 1.95 kJ

Answer 1

So the final solution is 65 g that has changed T from 25.0 to 30.0.
q = mass x specific heat x (Tfinal - Tinitial)
q = 65 x 4.18 J/g*C x (Tfinal - Tinitial)
Convert to kJ.