For pure water at 25 °C, K_w = 10⁻¹⁴. The concentration of OH⁻ in 10⁻³…

Question

For pure water at 25 °C, K_w = 10⁻¹⁴. The concentration of OH⁻ in 10⁻³ M HCl is

Accepted Answer

D. 10⁻¹¹ M

1. [H⁺] from HCl ≈ 10⁻³ M (water contribution negligible).
2. K_w = [H⁺][OH⁻] = 10⁻¹⁴, so [OH⁻] = 10⁻¹⁴ / 10⁻³.
3. [OH⁻] = 10⁻¹¹ M.
_Source: Maharashtra Balbharati Std XII Chemistry, Ch 3 "Ionic Equilibria" §3.6_

Answer

10⁻¹⁴ M

Answer

10⁻³ M

Answer

10⁻⁷ M