phy heat question

the specific latent of fusion of ice
= (40400-28000)J / 0.045kg
= 275556 J / kg
why should the ice used in the experiment be crushed?
In order to speed up the melting process and thus reduce the heat transfer from the environment to the experiment.
There is no 'specific latent of fusion of water', there is only specific latent of fusion of ice & specific latent of vapourization of water.
Specific latent of fusion of ice is the enthalpy (heat) change from the change of state from ice to liquid water.
Specific latent of vapourization of water is the enthalpy (heat) change from the change of state from liquid water to steam.
I hope this can help with your understanding. =)

2007-11-18 08:59:19 補充：
因為熱能不斷從周圍空間流入實驗中的系統，所以時間越長，熱力流入越多，即誤差越大。為減少誤差，實驗需要越短時間內完成。

ice melt to form water