NEET-XII-Chemistry
02: Solutions
- #12State
Henry’s law and mention some important applications?Ans : Henry’s law
states that partial pressure of a gas in the vapour phase is
proportional to the mole fraction of the gas in the solution. If p is the partial pressure of the gas in the vapour phase and x is the mole fraction of the gas, then Henry’s law can be
expressed as:
p = KH x
Where,
KH is
Henry’s law constant
Some important
applications of Henry’s law are mentioned below.
(i) Bottles are sealed under high pressure to increase the
solubility of CO2 in soft drinks and soda water.
(ii) Henry’s law states that the solubility of gases
increases with an increase in pressure. Therefore, when a scuba diver
dives deep into the sea, the increased sea pressure causes the
nitrogen present in air to dissolve in his blood in great amounts. As
a result, when he comes back to the surface, the solubility of
nitrogen again decreases and the dissolved gas is released, leading
to the formation of nitrogen bubbles in the blood. This results in
the blockage of capillaries and leads to a medical condition known as
‘bends’ or ‘decompression sickness’.
Hence,
the oxygen tanks used by scuba divers are filled with air and diluted
with helium to avoid bends.
(iii) The concentration of oxygen is low in the blood and
tissues of people living at high altitudes such as climbers. This is
because at high altitudes, partial pressure of oxygen is less than
that at ground level. Low-blood oxygen causes climbers to become weak
and disables them from thinking clearly. These are symptoms of
anoxia.