the hydroxide ion concentration in a sample of lemon juice is 1.9 x 10^-12 2.28 4.3 5.2 11.72 1.92 X 10^-12

[OH⁻] = 1.9 * 10⁻¹² M

Explanation:

The pH of lemon juice is 2.3. We can calculate the pOH using the following expression.

pH + pOH = 14

pOH = 14 - pH

pOH = 14 - 2.3 = 11.7

The pOH is 11.7. We can calculate the concentration of the hydroxide ion using its definition.

pOH = - log [OH⁻]

- pOH = log [OH⁻]

[OH⁻] = anti log ( - pOH)

[OH⁻] = anti log ( - 11.7)

[OH⁻] = 1.9 * 10⁻¹² M