Answer to Question #257715 in Chemistry for ashley

Question

5.00 g of sodium hydroxide is dissolved in 150 mL of water. Using a coffee-cup calorimeter, the temperature change of the water is measured to be 2.2 degrees celsius. The specific heat capacity of water is 4.184 J/g°C. Calculate the heat released per gram of sodium hydroxide dissolved.

Answer 1

Q = C x m x deltaT

density = m / V

Water density is 1 g/ml. Therefore, 150 ml of water is equal to 150 g.

Q = 4.184 x 150 x 2.2 = 1 380.1 J

The heat released per gram of sodium hydroxide dissolved equals to:

Q₁ = 1 380.1 / 5 = 276 J