Vodka is the most effective drink at melting ice because it has a low freezing point. The freezing point of vodka is -27 degrees Celsius, while the freezing point of water is 0 degrees Celsius. This means that vodka will remain liquid at a lower temperature than water, and it will therefore be able to melt ice more quickly.

In addition, vodka also has a low specific heat capacity. This means that it takes less energy to raise the temperature of vodka than it does to raise the temperature of water. This means that vodka will be able to absorb heat from the ice more quickly, and it will therefore be able to melt ice more quickly.

The combination of a low freezing point and a low specific heat capacity makes vodka the most effective drink at melting ice.