In a neutral solution, the concentration of __________.

• A. Hydrogen ions is less than the concentration of hydroxide ions.
• B. Water molecules is less than the concentration of hydroxide ions.
• C. Hydrogen ions is greater than the concentration of hydroxide ions.
• D. Hydrogen ions is equal to the concentration of hydroxide ions.

Answer: (D)

Verified step by step guidance

1. Understand the concept of a neutral solution: A neutral solution is one where the pH is 7, indicating that the solution is neither acidic nor basic.
2. Recall the definition of pH: pH is a measure of the hydrogen ion concentration in a solution. A pH of 7 means that the solution has equal concentrations of hydrogen ions (H⁺) and hydroxide ions (OH⁻).
3. Apply the concept of water dissociation: In pure water, a small number of water molecules dissociate into hydrogen ions (H⁺) and hydroxide ions (OH⁻). The equation for this dissociation is: <math xmlns='http://www.w3.org/1998/Math/MathML'><mrow><msub><mrow><mi>H</mi></mrow><mn>2</mn></msub><mi>O</mi><mo>&#x2194;</mo><msup><mi>H</mi><mo>+</mo></msup><mo>+</mo><msup><mi>OH</mi><mo>-</mo></msup></mrow></math>
4. Recognize the equilibrium condition: In a neutral solution, the concentrations of H⁺ and OH⁻ are equal because the dissociation of water is at equilibrium. This is represented by the equation: [H⁺] = [OH⁻].
5. Conclude with the correct statement: In a neutral solution, the concentration of hydrogen ions is equal to the concentration of hydroxide ions, which is why the solution is neither acidic nor basic.