Answer is : It is a good thermal and electrical conductor. -The main point to be noted is that aluminium is a highly reactive element and still it is used for making cooking utensils. The reason is that aluminium has a very high affinity for oxygen. So, it reacts with oxygen and forms a layer of aluminium oxide on its surface.
This is because aluminium reacts with oxygen present in air to form a thin layer of aluminium oxide . This oxide layer is very stable and prevents further reaction of aluminium with oxygen . Also , it is light in weight and a good conductor of heat Hence , it is used to make cooking utensils .
