First, find how many grams are in 1 mole of water.
For a hydrogen atom, there is about 1 gram per mole. For an oxygen atom, there are about 16 grams per mole.
In H2O, there are two hydrogen atoms and one oxygen atom. This means there are 18 grams in one mole of water. Multiply the mass in one mole by your number of moles.
18 x 11.8 = 212.4 grams
You have 212.4 grams of water.
When you want to melt an ice, you only need the latent energy of fusion, <span>δhfus. We use the given value, then multiply this with the given amount to determine the amount of energy. Since the energy is per mole basis, use the molar mass of ice which is 18 g/mol. The solution is as follows:
</span>ΔH = 5.96 kJ/mol * 1 mol/18 g * 500 g
<em>ΔH = 165.56 kJ</em><span>
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