Introduction:
Ice at 273 K (0°C) is more effective in cooling than water at the same temperature due to its specific heat capacity and latent heat of fusion.

Specific Heat Capacity:
- Specific heat capacity is the amount of energy required to raise the temperature of a substance by a certain amount.
- The specific heat capacity of ice is lower than that of water.
- This means that ice requires less energy to increase its temperature compared to an equal mass of water.
- As a result, ice can absorb more heat from its surroundings without experiencing a significant increase in temperature.

Latent Heat of Fusion:
- Latent heat of fusion is the amount of energy required to change a substance from a solid to a liquid state at its melting point.
- Ice has a higher latent heat of fusion compared to water.
- When ice absorbs heat, it undergoes a phase change and melts into water while maintaining its temperature at 0°C.
- This process requires a significant amount of energy, known as the latent heat of fusion.
- As a result, ice can absorb a larger amount of heat from its surroundings without experiencing a temperature rise, as the energy is utilized for the phase change rather than increasing the temperature.

Effective Cooling:
- When ice is placed in a warmer environment, it absorbs heat from the surroundings.
- As the ice absorbs heat, it undergoes a phase change and melts into water while staying at 0°C.
- The heat energy from the surroundings is utilized in breaking the intermolecular forces holding the ice molecules together, resulting in the solid-liquid phase change.
- As a result, the surroundings experience a cooling effect as the heat energy is transferred to the ice for the phase change process, rather than causing a rise in temperature.

Conclusion:
In conclusion, ice at 273 K is more effective in cooling than water at the same temperature due to its lower specific heat capacity and higher latent heat of fusion. These properties allow ice to absorb more heat from its surroundings without experiencing a significant increase in temperature, making it an effective cooling agent.

ice at 273k ( 0° c) is more effective in cooling because for melting ice a large amount of latent heat is needed and hence cools the substance more effectively. Water at the same temperature cannot take away any such latent heat from the substance and hence does not cool it more effectively