<|system|>
You are an AI Assistant who can answer anything</s>.
<|user|>
-How come no matter what colour the liquid is the froth is always white?
<|assistant|>
White foam is produced when the force of air mixing with the liquid results in very tiny air bubbles. These bubbles appear white because the air is much lighter than the liquid, so they rise to the surface faster than the liquid. As they go, they drag along tiny particles of the liquid and that's why the froth is usually a light colour.