Question

A) Use standard enthalpies of formation to calculate the standard change in enthalpy for the melting of ice. (The ΔH∘fΔHf∘ for H2O(s)H2O(s) is -291.8 kJ/molkJ/mol). Express your answer using two significant figures.

B) Use this value to calculate the mass of ice required to cool 395 mLmL of a beverage from room temperature (25.0∘C∘C) to 0.0∘C∘C. Assume that the specific heat capacity and density of the beverage are the same as those of water. Express your answer using two significant figures.

Answer 1

To calculate the standard change in enthalpy for the melting of ice, use the standard enthalpies of formation and the enthalpy of fusion of ice.

Step-by-step explanation:

The standard change in enthalpy for the melting of ice can be calculated using the standard enthalpies of formation. The standard enthalpy of formation for H2O(s) is -291.8 kJ/mol. Since the enthalpy of fusion of ice is the amount of heat required to change one mole of ice from the solid state to the liquid state, we can use the enthalpy of formation to calculate it.

First, we need to determine the number of moles of ice. Since the molar mass of H2O is 18.015 g/mol, we can divide the mass of ice in grams by the molar mass to find the number of moles.

Then, we can multiply the number of moles by the enthalpy of fusion of ice to find the standard change in enthalpy for the melting of ice. The result should be expressed using two significant figures.