A 10.000g ice cube is added to 100.000g of water at 80.0 oC in a calorimeter. The final temperature of the water in the calorimeter is 65.5 oC. How much heat in kilojoules was needed to melt the ice cube?

The amount of heat needed to melt the ice cube is 6.083 kJ

Explanation:

The processes involved in the given problem are:

To calculate the amount of heat required to melt the ice at its melting point, we use the equation:

where,

= amount of heat absorbed = ?

m = mass of ice = 10.000 g

= enthalpy change for fusion = 334.16 J/g

Putting all the values in above equation, we get:

To calculate the heat required at different temperature, we use the equation:

where,

= heat absorbed

m = mass of ice = 10.000 g

c = specific heat capacity of water = 4.184 J/g.°C

= change in temperature =

Putting values in above equation, we get:

Total heat absorbed =

Total heat absorbed =

Hence, the amount of heat needed to melt the ice cube is 6.083 kJ

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