Question

How much energy is required to melt a 500g block of iron if the heat of vaporization is 6090 J/g and the heat of fusion is 247 J/g?

a) 3.05x10⁶ J
b) 2.47x10² J
c) 1.23x10⁵ J
d) 6.09x10³ J

Answer 1

The energy required to melt a 500g block of iron is 123,500 J.

Step-by-step explanation:

To calculate the amount of energy required to melt the iron block, we need to consider both the heat of fusion and the heat of vaporization. First, we calculate the energy required to melt the block using the formula Q = m * heat of fusion, where Q is the energy, m is the mass, and the heat of fusion is 247 J/g. Therefore, the energy required to melt a 500g block of iron is 500g * 247 J/g = 123,500 J. Next, we calculate the energy required to vaporize the liquid iron using the formula Q = m * heat of vaporization, where Q is the energy, m is the mass, and the heat of vaporization is 6090 J/g. Since the iron is already in a liquid state after melting, the energy required to vaporize it is 0 J. Therefore, the total energy required to melt the iron block is 123,500 J.