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Manipal MET2012ChemistryThermodynamics (C)

A coffee cup calorimeter initially contains 125 g of water at a temperature of 24.2^ C . After adding of 10.5 g of KBr , the temperature becomes 21.1^ C . The heat of solution is

Options

  1. A40 ~J / g
  2. B117 ~J / g
  3. C167.7 ~J / g
  4. D420.05 ~J / g

Correct answer

C. 167.7 ~J / g

Step-by-step solution

aligned H & =m s T=(125+10.5) 1 3.1 & =420.05 cal = 420.05 10.5 cal / g & =40 cal / g =167.7 ~J / g aligned

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