A candle burning is an example of . a physical change

an exothermic change

energy being taken in

an endothermic change

Idon't understand what to put on the left lines i'm confused can anyone ?

Marcel just purchased 1.69 grams of iron fillings in order to make living putty for his 6 year old niece. how many moles of iron are made in his sample?

Some liquids can be distilled, but only at temperatures that are so high that it is impractical, or so high the compound decomposes. explain why distillation such compounds at significantly less than atmospheric pressure (some degree of vacuum) would solve this problem.