A napthelene hemisphere is placed on a glass plate and a napthelene ball of identical diameter is kept suspended in the stagnant air in two large rooms. The respective shapes of the ball are maintained while they sublime and reduce in size. Which of the following statements are true in this connection?

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asked Sep 21, 2022 in Mass Transfer by Julian (37.1k points)

A napthelene hemisphere is placed on a glass plate and a napthelene ball of identical diameter is kept suspended in the stagnant air in two large rooms. The respective shapes of the ball are maintained while they sublime and reduce in size. Which of the following statements are true in this connection?

(a) They take the same time for complete sublimation

(b) The sphere disappears first

(c) The hemisphere disappears first

(d) Nothing definite can be said

The question was asked in an online quiz.

The above asked question is from Diffusion through Variable Area topic in portion Diffusion in Solids and Molecular Diffusion in Fluids of Mass Transfer

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