using a coffee calorimeter, it is found that when an ice cube weighing 24.6g melts, it absorbs 8.19kJ of heat. calculate delta H for the phase change represented by the thermochemical equation: H2O(s) ->H2O(l)
q = mass x heat fusion.
8.19 kJ = 24.6 x heat fusion.
Remember this is + in going from solid to liquid.
To calculate ΔH for the phase change represented by the thermochemical equation H2O(s) -> H2O(l), you need to use the concept of heat transfer and the equation q = m·ΔH.
Given information:
- Mass of the ice cube (m) = 24.6g
- Heat absorbed (q) = 8.19kJ (Note: convert kJ to J by multiplying by 1000, since the mass is in grams)
To find ΔH, we will rearrange the equation q = m·ΔH to solve for ΔH.
ΔH = q / m
Substituting the given values:
ΔH = 8.19kJ / 24.6g
(Note: Convert the units of mass to kilograms to match the units of energy)
ΔH = 8.19kJ / (24.6g × 0.001kg/g)
ΔH = 8.19kJ / 0.0246kg
ΔH ≈ 333.33 kJ/kg
Therefore, the ΔH for the phase change represented by the thermochemical equation H2O(s) -> H2O(l) is approximately 333.33 kJ/kg.