For which of the following combinations, does the absorption operation become gas -film controlled?
- $P$. The solubility of gas in the liquid is very high
- $Q$. The solubility of gas in the liquid is very low
- $R$. The liquid-side mass transfer coefficient is much higher tan the gas-side mass transfer coefficient
- $S$. The liquid-side mass transfer coefficient is much lower than the gas-side mass transfer coefficient
- $\text{P & Q}$
- $\text{P &R}$
- $\text{P & S}$
- $\text{Q & R}$