Question

pH plays a very important role in our daily life. Most of the biochemical reactions taking place in our body are in a narrow pH range of 7.0 – 7.8. Small change in pH disturbs these process. Calculate the pH of 0.001 molar solution of HCl.

Answer 1

PH plays a very important role in our daily life. Most of the biochemical reactions taking place in our body are in a narrow pH range of 7.0 – 7.8. Small change in pH disturbs these process. Calculate the pH of 0.001 molar solution of HCl.

Answer 2

"pH of 0.001 molar solution of HCI is 3.

Solution:

In our day today life pH plays a major role. In digestion process Pepsin enzyme "acts in acidic medium" and trysin "acts in basic medium".

pH of blood is also an important aspect of pH in our body pH above or below the range can cause severe problems and may result in death.

HCl dissociate to give $H^+ and Cl^- ions$ and the dissociation of HCl is very high, so the "number of ions" is directly proportional to number of molecules present.

$\mathrm{pH}=-\log \left[\mathrm{H}^{+}\right]$ concentration of $H^+ ions$ is same as the concentration of HCI

pH=-log [0.001]

$\mathrm{pH}=-\log \left[1 \times 10^{-3}\right]$

$\mathrm{pH}=-\log 10^{-3}$

pH=-(-3)log10

$pH=3\times 1 (log10=1)$

pH=3"