Question

The pH of a soft drink is $3.82$. The hydrogen ion concentration wil be: (given antilog $0.18=1.5$)

• A. $1.96\times {10}^{-2}mol{lit}^{-1}$
• B. $1.96\times {10}^{-2}mol{lit}^{-1}$
• C. $1.5\times {10}^{-4}mol{lit}^{-1}$
• D. $1.5\times {10}^{-2}mol{lit}^{-1}$

Answer 1

The correct option is C $1.5\times {10}^{-4}mol{lit}^{-1}$

Formula:

$pH=-log\left[H^{+}\right]$

when $pH=3.82$

$\left[H^{+}\right]={10}^{-3.82}={10}^{-4+0.18}={10}^{0.18}\times {10}^{-4}=1.513\times {10}^{-4}$

Hydrogen ion concentration will be $\left[H^{+}\right]=1.5\times {10}^{-4}M$