Final answer:
The enthalpy of fusion (∆H) for the phase change of water from solid to liquid can be calculated using the formula ∆H = ∆Hf * n, where ∆Hf is the enthalpy of fusion per mole of substance and n is the number of moles of the substance. For water, the enthalpy of fusion is 334 kJ/kg. Therefore, for 1.40 moles of water, the ∆H is 26.13 kJ/mol.
Step-by-step explanation:
The process of water changing from solid to liquid is called melting or fusion. In this phase change, energy in the form of heat is absorbed by the water, causing the water molecules to gain enough energy to break free from their rigid arrangement in the solid state and move more freely in the liquid state. The amount of energy required for this phase change is known as the enthalpy of fusion (∆H). For water, the enthalpy of fusion is 334 kJ/kg. To calculate the ∆H for a given number of moles of water, you can use the formula:
∆H = ∆Hf * n
Where ∆H is the enthalpy of fusion, ∆Hf is the enthalpy of fusion per mole of substance, and n is the number of moles of the substance. In this case, since we have 1.40 moles of water, we can calculate the ∆H as follows:
∆H = (334 kJ/kg) * (1.40 mol/18.02 g) = 26.13 kJ/mol