J D factor for mass transfer is a function of Reynolds number. Mass tr – McqOptions

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1.	J D factor for mass transfer is a function of Reynolds number. Mass transfer by molecular diffusion from a single drop to surrounding still air is given by
A.	N sh = 2
B.	N st = 2
C.	N sc = 2
D.	none of these
Answer» B. N st = 2

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