Final answer:
The amount of heat needed to melt the ice cube is 16.7 kJ.
Step-by-step explanation:
To calculate the amount of heat needed to melt the ice cube, we can use the principle of energy conservation. The heat gained by the water is equal to the heat lost by the ice cube.
We know that the specific heat capacity of water is 4.184 J/(g·°C) and the heat of fusion of ice is 334 kJ/kg. Assuming the final temperature is 0°C after melting, we can calculate the heat needed:
Heat gained by water = Heat lost by ice cube
Mass of water × specific heat capacity of water × temperature change = Mass of ice cube × heat of fusion of ice
(100,000 g water) × (4.184 J/(g·°C)) × (65.5°C - 80.0°C) = (10,000 g ice cube) × (334,000 J/g)
Solving this equation, we find that the heat needed to melt the ice cube is 16.7 kJ.