Question

Solution (a) has a hydrogen ion concentration of 2.7 x 10^-3 and solution (b) has a hydrogen ion concentration of 4.1 M. What are their pH and say if they are acids or bases.

Answer 1

Answer: a) pH = 2.56 , acidic

b) pH = 2.38, acidic

Explanation:

pH or pOH is the measure of acidity or alkalinity of a solution.

pH is calculated by taking negative logarithm of hydrogen ion concentration.

$pH=-\log [H^+]$

a) $[H^+]=2.7\times 10^{-3}$

Putting in the values:

$pH=-\log[2.7\times 10^{-3}]$

$pH=2.56$

Thus as pH is less than 7, the solution is acidic.

b) $[H^+]=4.1\times 10^{-3}$

Putting in the values:

$pH=-\log[4.1\times 10^{-3}]$

$pH=2.38$

Thus as pH is less than 7, the solution is acidic.