Question

100.0 mL of 0.400 M aqueous NaOH and 50.00 mL of 0.400 M aqueous H2SO4, each at 24.00°C, were mixed, see equation:

2NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + 2H2O(l)

The final temperature achieved by the solution was 26.65 °C. Neglect the heat capacity of the cup and the thermometer, and assume that the solution of products has a density of exactly 1.00 g/mL and specific heat capacity of 4.18 J/(g•C)

How much heat did the reaction release?

Answer 1

Heat released by the reaction = Heat gaiend by solution

we can use the following formula

Q = mc∆T

Q = heat energy (Joules, J), m = mass of a substance (g)

c = specific heat (units J/g∙°C), ∆ is a symbol meaning "the change in"

∆T = change in temperature (°C Celcius)

Q = ? m = 100 ml + 50 ml = 150 ml = 150 g c = 4.18 J/g∙°C   ∆T = 26.65°C - 24 °C = 2.65  °C

Q =  150 g  x 4.18 J/g∙°C x 2.65  °C

Q = 1661.55 Joules

Hence 1661.55 joules of heat was released in the reaction