Question

What is the delta H fusion used to calculate volume of a liquid frozen that produces 1 kg of energy?

Answer 1

Answer:

The correct option is C. 1 kJ x 1/ΔHfus x g/mol x ml/g liquid

Explanation:

The change in enthalpy of fusion (ΔHfus) has units of energy divided into moles of substance:

ΔHfus = energy/mol of substance = J/mol or KJ/mol

Thus, we multiply the kJ of energy produced by the inverse of ΔHfus (in kJ/mol) we obtain the moles of substance:

energy (kJ) x 1/ΔHfus (mol/kJ) = moles of substance(mol)

Then, if we multiply the moles of substance by the molecular weight of the substance (in g/mol) we obtain the grams:

moles of substance(mol) x molecular weight (g/mol) = grams of substance (g)

Finally, if we multiply the grams of substance (in g) by the density of the substance (in g/ml) we obtain the volume (in ml):

grams of substance (g) x 1/density (ml/g) = volume (ml)

We combine all these parts to obtain the equation for the volume required to produce 1 kJ of energy:

energy (kJ) x 1/ΔHfus (mol/kJ) x molecular weight (g/mol) x 1/density (ml/g)

Therefore, the correct option is:

C → 1 kJ x 1/ΔHfus x g/mol x ml/g liquid

Answer 2

1 kJ x 1/ΔHfus x g/mol x ml/g liquid