NEET2011Chemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Assertion : Helium is used in diving apparatus. Reason : Solubility of helium is less in blood.
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion.
- BIf both assertion and reason are true but reason is not the correct explanation of assertion.
- CIf assertion is true but reason is false.
- DIf both assertion and reason are false.
Correct answer
A. If both assertion and reason are true and reason is the correct explanation of assertion.
Step-by-step solution
A mixture of 2 % O ₂ and 98 % He is used in diving apparatus which gives the same partial pressure of O ₂ as in normal air at 1 ~atm . Due to high partial pressure and greater solubility, N ₂ gets dissolved in blood and form bubbles (bends or decompression sickness). Hence, N ₂ is replaced by helium which is much less soluble in biological fluids.