The surface renewal frequency in Danckwerts' model of mass transfer is – McqOptions

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1.	The surface renewal frequency in Danckwerts' model of mass transfer is given by ( K L : mass transfer co-efficient)
A.	K L 2 . D A
B.	K L 2 . D A
C.	K L 2 / D A
D.	K L / D A 2
Answer» D. K L / D A 2

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