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Moderate

Condensation of Water

APCHEM-EXQ78L

The molar enthalpy needed to change liquid water to water vapor is 40.7 kJ/mol at 100$^o$C based on the equation:

$$H_2O_{(l)} \rightarrow H_2O_{(g)}$$

How much heat is gained/lost by the system when 6.00 grams of water vapor is condensed?

A

13.6 kJ

B

-13.6 kJ

C

-40.7 kJ

D

40.7 kJ