what is the final temperature of the mixture?

Question

If 50.0 g H2O at 13.6 °C is combined with 85.0 g H2O at 93.7 °C, what is the final temperature of the mixture? The specific heat capacity of water is 4.184 J/g·K.

a.56.1 °C
b.80.1 °C
c.26.1 °C
d.40.0 °C
e.64.0 °C

Answer 1

Use the equation:

mc(T2-T1) = - mc(T2-T1).

Plug in what you have for the two solutions, and solve for T2.

The negative sign is necessary on one side because one of the solutions will be gaining heat while the other is losing heat.