NEETChemistryThermodynamics (C)
What is the standard enthalpy of vaporization (∆ vap H) for water?
Options
- A∆ vap H= + 40.79 kJ mol–1
- B∆ vap H= – 393.5 kJ mol–1
- C∆ vap H= – 2802.0 kJ mol–1
- D∆ vap H= 435.0 kJ mol–1
Correct answer
A. ∆ vap H= + 40.79 kJ mol–1
Step-by-step solution
The standard enthalpy of vaporization (∆ vap H) for water is ∆ vap H = + 40.79 kJ mol–1. This represents the heat required to vaporize one mole of water at its boiling point under standard pressure.