Question

Assertion :ionic conductivities increase with increase of temperature and pressure. Reason: Viscosity of water decreases with increase of temperature and increases with the increases of pressure.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is D Both Assertion and Reason are incorrect

The following trends are seen at a given relatively low temperature :

(a) small ions exhibit an increase in conductivity with pressure.

(b) intermediate sized ions exhibit a conductivity maximum as a function of pressure.

(c) conductivity decreases monotonically with pressure for large ions.

With increase in temperature, the following changes are seen for ions of different sizes:

(a) small ions : the increase in λ is seen to change to a conductivity maximum at sufficiently high temperatures.

(b) intermdiate sized ions : there is shift of the maximum to lower pressures.

(c) larger sized ions : no change; only a decreasing trend is seen.