Answer:

Explanation:-
pH is the measure of acidity or alkalinity of a solution.
Acids have pH ranging from 1 to 6.9 and bases have pH ranging from 7.1 to 14.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://img.qammunity.org/2017/formulas/chemistry/high-school/9p2aoktrfyrswsdfh3xbgetuhore5bd1n7.png)
We are given:
Household bleach has a pH of 13

![[H^+]=antilog(-13)](https://img.qammunity.org/2017/formulas/chemistry/high-school/bup7cz2t864mdho6yed91326nkrm3uy1bg.png)
![[H^+]=10^(-13)](https://img.qammunity.org/2017/formulas/chemistry/high-school/a0otu376f5do79bhu0sa5it3b3zzz1mdff.png)
Thus
concentration in household bleach is
.