NaCl has a mc020-1.jpgHfus = 30.2 kJ/mol. What is the mass of a sample of NaCl that needs 732.6 kJ of heat to melt completely?

Chemistry

2 answers:

Sidana [21]2 years ago

8 0

Answer:

d.) 1417.7 on edge 2020

Explanation:

hope this helps!

lilavasa [31]2 years ago

5 0

Answer: The mass of the sample will be 1417.7 grams.

Explanation:

We are given:

$\Delta H_{fusion}=30.2kJ/mol$

This means that 1 mole of NaCl has an enthalpy of fusion of 30.2 kJ

1 mole of NaCl has a mass of 58.44 grams.

So, 30.2 kJ of heat is require for a mass 58.44 grams of NaCl

So, 732.6 kJ of heat will be required for = $\frac{58.44g}{30.2kJ}\times 732.6 kJ$ = 1417.65 grams of NaCl.

Hence, the mass of NaCl sample will be 1417.7 grams.

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