16. Laminar flow range of mixing speed is obtained for

A. Re_i<10
B. 10<Re_i<10⁴
c. Re_i >10⁴
D. None of these

17. Which of the following number is calculated from the diameter and peripheral speed of the impeller?

A. Reynolds number
B. Froude number
C. Power number
D. None of these

18. A higher liquid height will lead to a higher gas hold up by which the oxygen transfer rate will be

A. higher throughout the reactor
B. lower throughout the reactor
C. higher at the base of the reactor
D. lower at the base of the reactor

19. The main function of the dimples provided in the cooling jacket is to

A. increase the level of turbulence of the cooling water in the jacket
B. increase the residence time of the cooling water in the jacket
C. increase the cooling water-jacket wall boundary layer size
D. all of the above

20. The power required by an agitator operating in a gas-sparged system is

A. lesser than the power required by an impeller in operating at same speed in a gas free system
B. more than the power required by an impeller in operating at same speed in a gas free system
C. same as the power required by an impeller in operating at same speed in a gas free system
D. none of the above