Question

Low concentration of oxygen in the blood and tissues of people living at high altitude is due to ____________.

• A. Low atmospheric pressure
  
• B. Both low temperature and high atmospheric pressure
• C. High atmospheric pressure
  
• D. Low temperature

Answer 1

The correct option is A Low atmospheric pressure


1)Temperature: As the temperature increases, the kinetic energy of gases particles increases. Due to increase in the kinetic energy of gas particles, they can easily escape which results in the low concentration of gases in liquid. So, the lower temperature favour the dissolution of gases in liquid.

2) Pressure: As the pressure increases, the gaseous particles come closer and the solubility of gas in liquid increases. It can also be given by Henry’s law :

$p=K_H$ . 𝑥

where,

$p$ = Partial pressure of gas

$K_H$ = Henry’s law constant

$x$ = mole fraction of the gas

Hence, high pressure condition is favourable for greater concentration of gases in liquid

Temperature of human body is constant. The low concentration of oxygen in the blood and tissues of people living at high altitude is due to low atmospheric pressure. Because at high altitudes, the partial pressure of oxygen is less than at the ground level. Hence due to decrease in atmospheric pressure of oxygen, its concentration in blood and tissues of people is lower.

Hence, option (B) is correct.