Question

The heat required to melt a piece of copper is (82 x 10 ^5 J). The heat of fusion of copper is (2.05×10 ^5 J/ kg). What is the mass of the block?

Answer 1

Step-by-step explanation:

Givens

Heat of Fusion = 2.05 * 10^5 J / kg watch the units.

Heat to actually melt the copper = 82 10^5 J

Formula

Mass of copper = Heat / Heat of Fusion

Solution

Mass of copper = 82*10^5 J / (2.05 * 10^5 J / kg)

Mass of copper = 40 kg

Notice that the kg is in the denominator of the second fraction. The rules of fractions would tell you the 1/1 / / 1 /kg . You take the right fraction and turn it upside down and multiply. 1 / 1 * kg/1 = 1* kg / 1*1 which is just kg.

Answer 40 kg of copper