The enthalpy of solution (dissolving) of sodium hydroxide is given below. Determine the change in temperature of a coffee cup calorimeter containing 150 ml of water when 5.00 g NaOH (40.00 g/mol) is added to the container. You may assume that the solution has the same specific heat and density as water.

NaOH(s) → NaOH(aq) ΔH =-44.51 KJ

a. +8.87°C

b. +2.70 C

c. 2.70°C

d. 8.87°C

The change in temperature of a coffee cup calorimeter is 8.87°C.

Explanation:

Volume of the water = V = 150 g

Density of the water , d =1.0 g/mL

Mass of the water = M

Mass of solution = m = M = 150.0 g

Moles of NaOH =

Energy released when 0.125 moles of NaOH added in water = Q

1 kJ = 1000 J

Heat gained by water = Q' = -Q ( conservation of energy)

Specific heat of solution = c = 4.184 J/g°C

Change in temperature of the solution =

The change in temperature of a coffee cup calorimeter is 8.87°C.