What happens in a chemical reaction?

What happens in a chemical reaction?

• A. Substances separate into components
• B. A new product is formed
• C. Energy is always released
• D. It is a physical change only

Answer: (B)

A chemical reaction is a process where bonds are broken and new bonds form, transforming the starting substances into substances with different properties. That change in bonding leads to the creation of a new product with a different identity from the reactants, which is why a new product is formed. Energy changes aren’t fixed in one direction—some reactions release heat, others absorb it, and some involve little or no net energy change at the observed conditions—so the idea that energy is always released isn’t reliable. It’s not just a physical change, either, because the substances’ identities are altered, not merely their arrangement or state.

A chemical reaction is a process where bonds are broken and new bonds form, transforming the starting substances into substances with different properties. That change in bonding leads to the creation of a new product with a different identity from the reactants, which is why a new product is formed. Energy changes aren’t fixed in one direction—some reactions release heat, others absorb it, and some involve little or no net energy change at the observed conditions—so the idea that energy is always released isn’t reliable. It’s not just a physical change, either, because the substances’ identities are altered, not merely their arrangement or state.