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GrogVix [38]
3 years ago
12

A metallurgist has a 42.0-gram sample of an object of unknown composition. On testing it, the metallurgist finds that it takes 2

,878 joules of heat to melt it completely. What is the object's heat of fusion?
Chemistry
2 answers:
emmasim [6.3K]3 years ago
7 0

Answer: The object's heat of fusion is 68.52 Joules/gram.

Explanation:

Mass of the sample = 42 grams

Energy required to melt the sample completely = 2878 Joules

Q=m\times\Delta H_{fusion}

2878 Joules=42\times \Delta H_{fusion}

\Delta H_{fusion}=\frac{2878 Joules}{42 g}=68.52 Joules/gram

The object's heat of fusion is 68.52 Joules/gram.

Llana [10]3 years ago
5 0

Answer:

68.5 in sig figs 68.52 not in sig figs

Explanation:

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