A mixture of `SO_2, H_2 and Cl_2` can be separated by _____________ followed by _________.

Explanation

To separate a mixture of `SO2`, `H2`, and `Cl2`, we can follow these steps:

1. **Separation of SO2 and H2**:
- The first step is to separate sulfur dioxide (SO2) from hydrogen (H2). Since SO2 has a higher density than H2, we can utilize the method of **diffusion**. In diffusion, lighter gases move faster than heavier gases, allowing us to separate them based on their density differences.

2. **Separation of H2 and Cl2**:
- After separating SO2 from H2, the next step is to separate hydrogen (H2) from chlorine (Cl2). This can be achieved through **fractional evaporation**. In fractional evaporation, the gases are separated based on their boiling points. H2 has a lower boiling point compared to Cl2, so they will evaporate at different temperatures, allowing us to collect them in separate fractions.

...