ANS:C - both H⁺ and OH^- ions are present in very small but equal concentration.

In a neutral solution, both H⁺ (hydrogen ions) and OH⁻ (hydroxide ions) ions are present in very small but equal concentrations. Explanation:

• In water, a small fraction of water molecules undergo self-ionization, producing equal amounts of H⁺ and OH⁻ ions through the reaction: H₂O ⇌ H⁺ + OH⁻.
• In a neutral solution, the concentrations of H⁺ and OH⁻ ions are equal, and their product (H⁺ concentration multiplied by OH⁻ concentration) equals the dissociation constant for water, which is approximately 1 x 10^-14 M² at 25°C.
• This means that the concentration of H⁺ ions is equal to the concentration of OH⁻ ions, resulting in a neutral pH.