Answer to Question #151198 in General Chemistry for Javier

Question

Calculate the heat change in kilocalories for vaporization of 49 g of water at 100 C.

Please express answer as a positive value using two significant figures and include the appropriate units.

Answer 1

The heat of vaporization at $100 \ ^o C = 540\ \frac{cal}{g} = 0.54\ \frac{kcal}{g}$

The absorbed heat $= 49 \ g * 0.54\ \frac{kcal}{g} = 26.46\ kcal \approx 26\ kcal$

Answer: $26\ kcal$