Question

Materials A, B, and C are solids that are at their melting temperatures. Material A requires 200 J to melt 4 kg, material B requires 300 J to melt 5 kg, and material C requires 300 J to melt 6 kg. Rank the materials according to their heats of fusion. If multiple materials rank equally, use the same rank for each, then exclude the intermediate ranking (i.e. if objects A, B, and C must be ranked, and A and B must both be ranked first, the ranking would be A:Greatest, B:Greatest, C:Third greatest). If all materials rank equally, rank each as 'Greatest'.

Answer 1

Answer:

B: Greatest, A: Second greatest, C: Second geratest.

Explanation:

We can calculate the heat of fusion of a material (ΔHfus), which is the heat required to melt 1 kg of material, using the following expression.

ΔHfus = Q/m

where,

• Q: heat provided

• m: mass

Material A

ΔHfus = 200 J/4 kg = 50 J/kg

Material B

ΔHfus = 300 J/5 kg = 60 J/kg

Material C

ΔHfus = 300 J/6 kg = 50 J/kg

Then, considering the heats of fusion,

B: Greatest, A: Second greatest, C: Second greatest.