Question

What is the H3O+ in a 0.0150M soloution of NaOH If Kwis 100*10^-14

Answer 1

The concentration of H3O+ in the solution is 6.667*10^-11M.

1st) From the dissociation equation of NaOH we calculate the concentration of OH- in the 0.0150M solution:

`\text{NaOH }\rightarrow Na^(1+)+OH^(-1)`

According to the equation, from 1 mol of NaOH we obtain 1 mol of OH-, so from the 0.0150M solution, we will obtain a 0.0150M concentration of OH-.

2nd) Using the Kw formula and replacing the values, we can calculate the H3O+ concentracion:

`\begin{gathered} K_w=\lbrack H_3O^+\rbrack\cdot\lbrack OH^-\rbrack \\ 100\cdot10^(-14)=\lbrack H_3O^+\rbrack\cdot0.0150M \\ (100\cdot10^(-14))/(0.0150M)=\lbrack H_3O^+\rbrack \\ 6.667\cdot10^(-11)=\lbrack H_3O^+\rbrack \end{gathered}`

So, the concentration of H3O+ in the solution is 6.667*10^-11M.