Question

when Zink oxide is hot​

Answer 1

Answer:

Zink oxide is heated in air

and when it becomes hot it's

colour changes into yellow colour

Answer 2

Zinc Oxide is originally a white powder. When heated up, it turns yellow but does not decompose and when it is removed from the heat it gradually goes back to its original white color. If you heat it strongly enough to very high temperatures it will sublime without apparent decomposition.