13. what is the concentration of hydronium and hydroxide ions in pure water at 25 ⁰c? 1.0 x 10⁻⁷ each 1.0 x…

13. what is the concentration of hydronium and hydroxide ions in pure water at 25 ⁰c? 1.0 x 10⁻⁷ each 1.0 x 10⁻¹⁴ each 1.0 x 10⁻⁷ and 1.0 x 10⁻¹⁴ respectively 1.0 x 10⁻¹⁴ and 1.0 x 10⁻⁷ respectively
Answer
Explanation:
Step1: Recall ion - product constant of water
The ion - product constant of water $K_w=[H_3O^+][OH^-]$, and at $25^{\circ}C$, $K_w = 1.0\times10^{- 14}$.
Step2: Consider pure water condition
In pure water, $[H_3O^+]=[OH^-]$. Let $x = [H_3O^+]=[OH^-]$. Then $K_w=x\times x=x^{2}$.
Step3: Solve for the concentration
Since $K_w = 1.0\times10^{-14}=x^{2}$, we take the square - root of both sides: $x=\sqrt{1.0\times10^{-14}} = 1.0\times10^{-7}\ M$. So $[H_3O^+]=[OH^-]=1.0\times10^{-7}\ M$.
Answer:
1.0 x 10⁻⁷ each