how much heat is needed to melt a 50- gram 0 degrees celcius sample of ice that is placed in a glass beaker containing 200g of water at 20 degrees celcius?
To calculate the amount of heat needed to melt the ice, we need to consider two components: the heat absorbed by the ice to reach its melting point (0 degrees Celsius), and the heat needed to melt the ice once it reaches its melting point.
1. Heat absorbed to reach the melting point:
To raise the ice from 0°C to 0°C (its melting point), we need to calculate the heat using the specific heat capacity of ice.
The specific heat capacity of ice is 2.09 J/g°C.
Mass of ice = 50g.
Temperature change = 0 - 0 = 0°C.
Heat absorbed = mass × specific heat capacity × temperature change
Heat absorbed = 50g × 2.09 J/g°C × 0°C
Heat absorbed = 0 J
So, no heat is absorbed during the phase change from solid ice to water at its melting point.
2. Heat needed to melt the ice:
To calculate the heat required to melt ice at its melting point, we use the heat of fusion of ice.
The heat of fusion of ice is 333.55 J/g.
Heat needed to melt = mass × heat of fusion
Heat needed to melt = 50g × 333.55 J/g
Heat needed to melt = 16677.5 J
Therefore, 16,677.5 Joules of heat is needed to melt the 50-gram sample of ice.
Please note that this calculation does not take into account any heat transfer losses to the surroundings, assuming an ideal scenario.