thermochemisrty

Question

Silicon, used in computer chips, has a heat capacity of 0.712 J·g^-1·°C^-1. If 500 J of heat is absorbed by 8.86 g of silicon, what will the final temperature be if the initial temperature is 22.9 °C?

Answer 1

We can use the equation q = mC∆T

q = heat = 500 J

m = mass = 8.86 g

C = specific heat of silicon = 0.712 J/g/deg

∆T = change in temperature = ?

500 J = (8.86 g)(0.712 J/g/deg)(∆T)

∆T = 500 J/(8.86 g)(0.712 J/g/deg) = 79.3 degrees

This is the CHANGE in temperature, not the final temperature.

Final temperature = 22.9º + 79.3º = 102.2ºC (note heat is added to initial temperature because heat was absorbed)