7. For laminar flow, Reynolds number is correlated with power number as (where K, a constant which depends on the container geometry and shape of stirrer; Rei is Reynolds number for agitator; Di, stirrer diameter and N, stirrer speed)
9. What is the effect of the concentration of dissolved salts and sugars on the oxygen transfer rate?
Options
A. The saturation concentration of oxygen in the medium decreases with the concentration of dissolved salts and sugars, leading to a lower oxygen transfer rate
B. The KLa of the medium decreases with the concentration of dissolved salts and sugars, leading to a lower oxygen transfer rate
C. The KLa of the medium increases with the concentration of dissolved salts and sugars, leading to a lower oxygen transfer rate
Correct Answer: The saturation concentration of oxygen in the medium decreases with the concentration of dissolved salts and sugars, leading to a lower oxygen transfer rate
10. The power required by an agitator operating in a gas-sparged system is
Options
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