The answer is: (5696 J) / (155 g) / (40.0 - 25.0)°C = 2.45 J/g·°C
The solution of Ba(OH)2 will have the lowest freezing point. This is because it dissociates into 3 ions, one Ba and 2 OH, which is more than any of the others. Freezing point depression is a colligitive property of water that depends, in part, on the number of ions.
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Molar mass Chlorine ( Cl ) = 35.45 g/mol
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