Question

Which statement provides the most accurate evidence to support the claim that chemical reactions play a role in energy transfer?

a) Chemical reactions release energy in the form of heat.
b) Chemical reactions involve the breaking and forming of bonds.
c) Chemical reactions only occur in living organisms.
d) Chemical reactions are always spontaneous.

Answer 1

Chemical reactions involve the exchange of energy, and the amount of energy released or absorbed determines the nature of the reaction.

Step-by-step explanation:

Chemical reactions always involve energy. Energy is a property of matter that is defined as the ability to do work. When methane burns, for example, it releases energy in the form of heat and light. Other chemical reactions absorb energy rather than release it.

One characteristic of a living organism is metabolism, which is the sum total of all of the chemical reactions that go on to maintain that organism's health and life. Both anabolic and catabolic chemical reactions involve exchanges of matter and energy.

The balance between the energy needed to break bonds and the energy released from forming new bonds determines whether the chemical reaction releases or absorbs energy. Chemical reactions that release energy are called exothermic reactions, and ones that absorb energy are called endothermic reactions.