chemistry
posted by Kamila .
The ΔH for the solution process when solid sodium hydroxide dissolves in water is 44.4 kJ/mol. When a 13.9 g sample of NaOH dissolves in 250.0 g of water in a coffeecup calorimeter, the temperature increases from 23.0°C to ________°C. Assume that the solution has the same specific heat as liquid water: 4.18 J/g•°C.

How much heat(q) does the NaOH provide? That is 44.4 kJ/mol or 44.4 kJ/40 g and you have 13.9 g; therefore, q = 44,400 x (13.9/40) = ??
Then q = mass water x specific heat water x (TfinalTinitial). Solve for Tfinal. The answer is approximately 35 C.