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oee [108]
3 years ago
7

calculate the amount of heat energy required to evaporate 25.7g of water at 100 degrees celcius. (Molar heat of vaporization of

liquid water= 4.07x10^4 J/mol)
Chemistry
1 answer:
Vikentia [17]3 years ago
8 0

Answer:

5.82 ×10⁴ j

Explanation:

Given data:

Mass of water = 25.7 g

Amount of heat to evaporate it = ?

Molar heat of vaporization = 4.07×10⁴ j/mol

Solution:

First of all we will calculate the number of moles of water.

Number of moles = mass/ molar mass

Number of moles = 25.7 g/ 18 g/mol

Number of moles = 1.43 mol

Energy needed for one mole is 4.07×10⁴ j.

For 1.43 mol:

1.43 mol × 4.07×10⁴ j/ 1mol

5.82 ×10⁴ j

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