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Q.
The $pH$ of a solution is increased from $3$ to $6$ , its $H ^{+}$ ion concentration will be
ManipalManipal 2011
Solution:
When $pH =3$ then $\left[ H ^{+}\right]=10^{-3} M$. After that we increased the $pH$ from $3$ to $6$ then $\left[ H ^{+}\right]=10^{-6} M$ means reduced $1000$ times.