Let’s figure out the amount of energy required to melt 2 kg of gold using the provided information.
We are given the equation for the heat required to change the phase of a substance, [tex]\( Q = m \cdot L_{\text{fusion}} \)[/tex], where:
- [tex]\( Q \)[/tex] is the heat energy required.
- [tex]\( m \)[/tex] is the mass of the substance.
- [tex]\( L_{\text{fusion}} \)[/tex] is the latent heat of fusion of the substance.
From the table provided, we know the latent heat of fusion for gold is [tex]\( L_{\text{fusion}} = 62.8 \, \text{kJ/kg} \)[/tex].
Using the given values:
- [tex]\( m = 2 \, \text{kg} \)[/tex]
- [tex]\( L_{\text{fusion}} = 62.8 \, \text{kJ/kg} \)[/tex]
We can now substitute these values into the equation:
[tex]\[ Q = m \cdot L_{\text{fusion}} = 2 \, \text{kg} \times 62.8 \, \text{kJ/kg} \][/tex]
Performing the multiplication:
[tex]\[ Q = 2 \times 62.8 = 125.6 \, \text{kJ} \][/tex]
Therefore, the amount of energy required to melt 2 kg of gold is [tex]\( 125.6 \, \text{kJ} \)[/tex].
The correct answer is:
A. 125.6 kJ
