Final answer:
To determine the energy required to heat 85.0 g of ice at -12.0 °C to steam at 121.0 °C, one must perform calculations for each phase change and temperature change using the specific heat capacities and heat of fusion and vaporization values.
Step-by-step explanation:
To calculate how much energy is needed to heat 85.0 g of H2O(s) at -12.0 °C to H2O(g) at 121.0 °C, we must consider the heat needed for warming the solid ice to 0 °C, the heat of fusion to turn the ice into liquid water, the heat required to increase the temperature of the water to 100 °C, the heat of vaporization to convert the liquid water to steam, and the heat needed to raise the temperature of the steam to 121 °C. The specific heat of ice, water, and steam, as well as the heat of fusion and vaporization values, would be required for these calculations. The equation used to calculate the heat absorbed during a temperature change is q = mcΔT, where q is the heat absorbed, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature.