4. Overall mass transfer co-efficient in case of absorption of __________ in water is based on the gas film co-efficient only, as the mass transfer process is gas film (phase) controlling.
6. For identical situation, condensing film coefficient in case of a horizontal condenser is almost __________ the value expected in case of vertical condenser.
7. A single pass air heater is connected to a two pass unit. For the air flow rate and other conditions remaining the same, the film heat transfer co-efficient for air will vary in the ratio of