To calculate the amount of heat that must be removed from the water, you can use the formula:
Q = m * C * ΔT
Where: Q is the heat energy m is the mass of the water (200 g) C is the specific heat capacity of water (4.18 J/g°C) ΔT is the change in temperature (30°C - 0°C = 30°C)
Plugging in the values:
Q = 200 g * 4.18 J/g°C * 30°C
Q = 25020 J
Therefore, you would need to remove 25,020 Joules of heat from the 200 grams of water at 30°C to cool it to 0°C.