For water, the value for the latent heat of vaporization is 6.8 times greater than the latent heat of fusion. Imagine we were adding heat at a constant rate to a block of ice in a beaker on a hot plate, and it took 4 minutes for the ice to melt completely. How long would it take, after the water started boiling, for the beaker to be completely empty (the liquid water totally converted to water vapor)?

The latent heat of fusion is the heat required to change the substance from solid (ice) to liquid completely, without further increase in temperature.

The latent heat of vaporization is the heat required to change a liquid to gas completely, without an increase in temperature.

Latent heat of vaporization = 6.8 times Latent heat of fusion

This means that the time it takes for the latent heat of vaporization to complete vaporization is 6.8 times lesser than the time it takes for the latent heat of fusion to complete fusion

Time of vaporization = 6.8 times lesser than time of fusion

Time of vaporization = (time of fusion) ÷ 6.8

where: Time of fusion = 4 minutes

∴ Time of vaporization = 4 ÷ 6.8

Time of vaporization = 0.588 minutes