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MHT CET20244 May 2024Evening ShiftChemistryThermodynamics (C)Actual

Calculate heat required to convert 9 g of liquid water to water vapours from following equations. aligned & H _ 2_ ( g ) + 1 2 O _ 2_ ( g ) H ₂ O _ ( g ) H =-57 kCal & H _ 2_ ( g ) + 1 2 O _ 2_ ( g ) H ₂ O _ ( g ) H =-68.3 kCal aligned

Options

  1. A5.65 k Cal
  2. B6.28 k Cal
  3. C7.05 k Cal
  4. D9.72 k Cal

Correct answer

A. 5.65 k Cal

Step-by-step solution

Given: - Mass of water: 9 g , - H for H ₂ O ( l ) H ₂ O ( g )=68.3 kCal / mol -57 kCal / mol =11.3 kCal / mol . Moles of Water: Moles = Mass Molar Mass = 9 18 =0.5 ~mol . Heat Required: Heat = Moles H=0.5 11.3=5.65 kCal Answer: 5.65 kCal, Option 1.

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