Question

The INCORRECT statement about the characteristics of critical point of a pure substance is that

• A. saturated liquid and saturated vapor states are identical
• B. it has point of inflection with zero slope
• C. there is no constant temperature vaporization process
• D. the ice directly converts from solid phase to vapor phase

Answer 1

The correct option is D the ice directly converts from solid phase to vapor phase

The characteristics of critical points of a pure substance.

(i) There is no constant temperature vapourization because heat of vapourization is zero

(ii) Critical point is point of inflection i.e., isothermal curve changes its curvature.

(iii) Liquid directly converts into vapour and when ice directly converts into vapour, it is known as sublimation.

(iv) Saturated liquid and saturated vapour states are identical.