Question

The subatomic particle which increases or decreases in an atom during the chemical reaction is(are) ________.

• A. proton
• B. neutron
• C. electron
• D. all of the above

Answer 1

Answer: (C)

electron

In a chemical reaction involving bond formation, only the outer-shell electrons (valence electrons) which have low ionization energy can participate and the nucleus remains intact. Thus electron participates in the chemical reaction while protons and neutrons remain unchanged.

Hence, the correct option is $\text{C}$