Question

copper metal has a specific heat of 0.385 j/g °c. calculate the amount of heat required to raise the temperature of 22.8 g of copper from 20.0 °c to 875 °c.
7.84 kj
10.5 kj
1.97 kj
7.51 kj
3.29 kj

Explanation:

Step1: Calculate temperature change

$\Delta T=T_{final}-T_{initial}=875 - 20.0=855^{\circ}C$

Step2: Use heat formula

The formula for heat $q = mc\Delta T$, where $m = 22.8g$, $c=0.385J/g^{\circ}C$, $\Delta T = 855^{\circ}C$
$q=22.8\times0.385\times855$
$q = 22.8\times(0.385\times855)$
First calculate $0.385\times855 = 329.175$
Then $q=22.8\times329.175=7505.19J$
Convert to kJ: $q=\frac{7505.19}{1000}=7.50519kJ\approx7.51kJ$

Answer:

7.51 kJ