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A 58.0 g sample of water vapor is condensing at 100.0 °C. Over time, all the water vapor is converted to liquid water at a temperature of 58 °C.

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The total heat released during the process of condensing 58.0 g of water vapor at 100.0 °C to liquid water at 58.0 °C is approximately 131.244 kJ.

How to find total heat?

To calculate the total heat released during the process of condensing water vapor to liquid water, we can use the formula:


\[ Q = m \cdot \Delta H \]

where:

Q = heat released,

m = mass of the substance (water in this case),

ΔH = enthalpy change for the phase transition.

For the condensation of water vapor to liquid water, the enthalpy change (ΔH) is the heat of vaporization (
\( \Delta H_{\text{vap}} \)).

Given:

Mass of water vapor (m) = 58.0 g

Heat of vaporization (
\( \Delta H_{\text{vap}} \)) for water at 100 °C =
\( 40.79 \, \text{kJ/mol} \)

First, find the moles of water vapor using the molar mass of water (
\( H_2O \)):


\[ \text{Molar mass of } H_2O = 18.015 \, \text{g/mol} \]


\[ \text{Moles of } H_2O = \frac{\text{Mass}}{\text{Molar mass}} = \frac{58.0 \, \text{g}}{18.015 \, \text{g/mol}} \]

Now, calculate the heat released:


\[ Q = \text{Moles} * \Delta H_{\text{vap}} \]


\[ Q = \left(\frac{58.0 \, \text{g}}{18.015 \, \text{g/mol}}\right) * (40.79 \, \text{kJ/mol}) \]


\[ Q = \text{Moles} * \Delta H_{\text{vap}} \]


\[ Q = (3.218 \, \text{mol}) * (40.79 \, \text{kJ/mol}) \]


\[ Q \approx 131.244 \, \text{kJ} \]

So, the total heat released during the process of condensing 58.0 g of water vapor at 100.0 °C to liquid water at 58.0 °C is approximately 131.244 kJ.

Complete question:

A 58.0 g sample of water vapor is condensing at 100.0 °C. Over time, all the water vapor is converted to liquid water at a temperature of 58 °C. Calculate the total heat released during this process.

User Tmaric
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