Question

Value of pH of a solution is 4. If indicates that concentration of hydrogen ions is

• A. ${10}^{-4}\text{g/litre and the solution is acidic}$
• B. ${10}^{-4}\text{g/litre and the solution is alkalite}$
• C. ${10}^{-4}\text{mg/litre and the solution is acidic}$
• D. ${10}^{-4}\text{mg/litre and the solution is alkalite}$

Answer 1

The correct option is A ${10}^{-4}\text{g/litre and the solution is acidic}$

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

$\text{4 = -log}\left[H^{+}\right]$

$\therefore \left[H^{+}\right]={10}^{-4}gm/litre$

$\text{Since, pH < 7 therefore it is ACIDIC.}$

$\therefore pH=-lo{g}_{10}{10}^{-4}=4$