Ice at 273 K (0°C) is more effective in cooling than water at the same temperature because it absorbs latent heat of fusion as it melts. This absorption of heat from the surroundings, without a change in temperature, leads to a more significant cooling effect compared to water, which does not undergo a phase change at this temperature.
Here’s a more detailed explanation:
Latent Heat of Fusion:
Ice at its melting point (273 K) needs to absorb a specific amount of energy to transition from solid to liquid (water). This energy is called the latent heat of fusion.
Cooling Effect:
As ice melts, it absorbs this latent heat from the surrounding environment, causing a decrease in the temperature of that environment. This is why ice is used in cooling applications.
Water at 273 K:
Water at the same temperature does not undergo a phase change and therefore does not absorb the latent heat of fusion. It may still transfer some thermal energy (heat) to a cooler object, but the cooling effect is less significant than that of melting ice.