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2 years ago

The molar heat of vaporization for water is 10.79 kJ/mol. How much energy must be absorbed by 100 grams

Chemistry

1 answer:

Andrei [34K]2 years ago

5 0

<h3>Answer:</h3>

59.87 kJ

<h3>Explanation:</h3>

In the question , we are given;

Molar heat of Vaporization as 10.79 kJ/mol
Mass of water at 100°C is 100 g

We are required to calculate the amount of heat energy absorbed to convert water at 100°C to steam at 100°C.

The process of converting water from liquid state to solid state without change in temperature is known as condensation.
We are given the molar heat of vaporization as 10.79 kJ/mol, this means 1 mole of water will absorb 10.79 kJ when converted to ice without change in temperature.

Therefore, we can first calculate the number of moles of water;

Moles = Mass ÷ Molar mass

Molar mass of water = 18.02 g/mol

Moles of water = 100 g ÷ 18.02 g/mol

= 5.549 moles

But;

Q = n × ΔHv , where n is the number of moles and ΔHv molar heat of Vaporization.

Therefore;

Q = 5.549 moles × 10.79 kJ/mol

= 59.874 kJ

= 59.87 kJ

Thus, the amount of heat absorbed is 59.87 kJ

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<em />

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