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What are the values of #DeltaH# and #DeltaS# for the change from gaseous to liquid #H_2O#?

Answer 1

For the process... #H_2O(g) rarr H_2O(l)+Delta#

AS written, #DeltaH# should be negative (i.e. heat should be a product of the reaction), and ALSO #DeltaS^@# should be NEGATIVE, because we go from a gaseous phase to a condensed phase, which minimizes the probability of disorder.

You can find the actual values for the processes in your text.

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Answer 2

Wyatt Atkins

The standard enthalpy change (ΔH) for the change from gaseous to liquid H2O is approximately -40.8 kJ/mol, and the standard entropy change (ΔS) is approximately 69.9 J/(mol·K).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.