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why does when boiled all liquids boil whereas just milk splits???
Good Question

Unlike water, milk is not a simple liquid. It is a colloid and contains many substances in suspended form. These substances are mainly protein, sugar and fat. When milk is heated slowly, the proteins and fat get separated. Since they are lighter than the milk they collect on the surface in the form of a layer called cream.Milk also has a large quantity of water in it. During heating some water gets converted into water vapour. The water vapour being lighter, rises up.

As the upper layer of the milk is covered with cream, the vapour gets trapped below it. As the milk is heated further, the water vapour expands and thick foam is produced on top.

Finally, the trapped vapour lifts the layer of cream up, quite like a hot air balloon, and finally bursts through this layer. As the vapour escapes, a lot of cream and milk spill out.


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