Ncert Exercises & Solutions

7.55 Calculate the hydrogen ion concentration in the following biological fluids whose pH are given below:

(a) Human muscle-fluid, 6.83 (b) Human stomach fluid, 1.2

(a) Human muscle fluid 6.83:

$pH = 6.83 pH = - \log [H^{+}]$
$6.83 = - \log [H^{+}]$
$[H^{+}] = 1.48 \times 10^{- 7} M$

(b) Human stomach fluid, 1.2:

$pH = 1.2$
$1.2 = - \log [H^{+}]$
$[H^{+}] = 0.063$

(c) Human blood, 7.38:

$pH = 7.38 = - \log [H^{+}]$
$[H^{+}] = 4.17 \times 10^{- 8} M$

(d) Human saliva, 6.4:

$pH = 6.4$
$6.4 = - \log [H^{+}]$
$[H^{+}] = 3.98 \times 10^{- 7}$