Question

The melting point of uranium is 1132°C, and the enthalpy of fusion (melting) of uranium is 9.14 kJ/mol. What is the entropy of fusion in J/(mol·K) of uranium?

a) 14.3
b) 154
c) 6.50
d) 9.14

Answer 1

c) 6.50

The entropy of fusion of uranium is 6.50 J/(mol·K), calculated by dividing the enthalpy of fusion by the melting point in Kelvin.

Step-by-step explanation:

To calculate the entropy of fusion of uranium, we need to use the formula ΔSfus = ΔHfus / T₏us, where ΔHfus is the enthalpy of fusion and T₏us is the melting point in Kelvin.

The given melting point of uranium is 1132°C, which needs to be converted to Kelvin (1132 + 273.15 = 1405.15 K).

The enthalpy of fusion is given as 9.14 kJ/mol.

When we plug these values into the formula,

we get ΔS₏us = 9.14 kJ/mol / 1405.15 K = 0.00650 kJ/(mol·K) or 6.50 J/(mol·K),

as we convert kJ to J by multiplying by 1000.