Given that K w Kw for water is 2.4 × 10 − 14 M 2 2.4×10−14 M2 at 37 37 °C, calculate the pH of a neutral aqueous solution at 37 37 °C, which is the normal human body temperature.

Explanation:

1. Kw expression

Kw is the dissociation, also known as self-ionization, constant of water. this is an equilibrium constant, and its expression is:

           Kw = [OH⁻] . [H₃O⁺]

2. Neutral pH

Neutral pH means that the concentrations of OH⁻ and H₃O⁺ are equal.

Call them x, to calculate the it:

       Kw =[OH⁻] . [H₃O⁺] = x²

3. Solve the equation:

       x² = 2.4 × 10⁻¹⁴ M²

       x = 1.5919 × 10⁻⁷ M

Thus, x = [H₃O⁺] = [OH⁻] = 1.5919×10⁻⁷ M

4. Calculate pH