The increasing order of crystal field splitting strength of the given ligands is

Options

A. `NH_3 lt Cl^(-) lt CN^(-) lt F^(-) lt CO lt H_2O`
B. `F^(-) lt Cl^(-) NH_3 lt CN^(-) lt H_2O lt CO`
C. `Cl^(-) lt F^(-) lt H_2O lt NH_3 lt CO`
D. `CO lt CN^(-) NH_3 lt H_2O lt F^(-) lt Cl^(-)`

Answer

To determine the increasing order of crystal field splitting strength of the given ligands, we will utilize the spectrochemical series, which ranks ligands based on their ability to split the d-orbitals in transition metal complexes.

### Step-by-Step Solution:

1. **Understand the Spectrochemical Series**: The spectrochemical series is a list that ranks ligands according to the strength of the crystal field splitting they induce in a metal complex. The stronger the ligand, the greater the splitting of the d-orbitals.

2. **List the Ligands**: From the video transcript, we have the following ligands mentioned:
- NH3
- SCN^-
- H2O
- OH^-
- F^-
- Cl^-
- S^2-
- Br^-
- I^-

3. **Rank the Ligands**: According to the spectrochemical series, the ligands can be arranged in the following increasing order of crystal field splitting strength:
- I^- < Br^- < Cl^- < F^- < OH^- < H2O < NH3 < SCN^- < CN^-

4. **Identify the Correct Order**: From the above arrangement, we can see that the ligands can be categorized from weak to strong field ligands. The increasing order of crystal field splitting strength is:
- I^- < Br^- < Cl^- < F^- < OH^- < H2O < NH3 < SCN^-

5. **Conclusion**: The final answer for the increasing order of crystal field splitting strength of the given ligands is:
- I^- < Br^- < Cl^- < F^- < OH^- < H2O < NH3 < SCN^-