The correct answers are options C, that is, silver tarnishes and becomes black when exposed to oxygen, and option E, that is, diesel fuel burns when it is heated.
Explanation:
Chemical changes refer to the modifications in which the chemistry at molecular level is modified as the initial substance gets transformed into a new and different final substance. This change occurs with the dissociation of old bond and production of new bonds respectively.
The body needs to maintain the amount of oxygen that reaches our cells. If we exercise a lot, our breathing rate increases. More oxygen enables our cells to <span>more quickly respire aerobically, so that our muscles can contract more rapidly.
