Absorption factor is defined as (where, S₁ = slope of the operating line S₂ = slope of the equilibrium curve)

ANS:B - S₁/S₂

The absorption factor is defined as S2/S1. Explanation:

1. Definition:
   • The absorption factor is a parameter used in absorption processes to quantify the efficiency of the mass transfer of a solute from a gas phase into a liquid phase.
   • It represents the ratio of the slope of the equilibrium curve (S2) to the slope of the operating line (S1).
2. Operating Line and Equilibrium Curve:
   • In absorption processes, the operating line represents the relationship between the concentrations of the solute in the gas and liquid phases as they change along the height of the absorber.
   • The equilibrium curve represents the equilibrium relationship between the concentrations of the solute in the gas and liquid phases at each stage of the absorber.
   • The slopes of the operating line (S1) and equilibrium curve (S2) are determined based on the specific operating conditions and properties of the system.
3. Absorption Factor Calculation:
   • The absorption factor is calculated by taking the ratio of the slope of the equilibrium curve (S2) to the slope of the operating line (S1).
   • Mathematically, it is expressed as S2/S1.
4. Significance:
   • A higher absorption factor indicates that the system is more efficient at transferring the solute from the gas phase into the liquid phase.
   • It reflects the ease with which the solute can be absorbed by the solvent under the given operating conditions.