Question

How much energy is needed to melt 161.0 g of ethanol(C₂H₅OH)?(Heat of fusion Ethanol- 5.02 KJ/mol)

Answer 1

Answer:

17.6kJ

Explanation:

The mass of ethanol given is 161.g

 Now we first find the number of moles from this.

 Number of moles  = $\frac{mass}{molar mass}$

            Molar mass of C₂H₅OH = 2(12) + 5(1) + 16 + 1  = 46g/mol

Number of moles of ethanol  = $\frac{161}{46}$   = 3.5mol

Since the heat of fusion is  5.02kJ/mol;

       Heat of fusion is a measure of the amount of energy needed to melt a substance.

  Amount of energy needed to melt =  3.5mol x  5.02kJ/mol

                                                             = 17.6kJ