Mark the correct statement

Options

A. I group basic radicals precipitate as chlorides
B. IV group basic radicals precipitate as sulphides
C. V groups basic radicals precipitate as carbonates
D. All of these statement are correct

Answer

To solve the question of marking the correct statement regarding the precipitation of basic radicals in analytical chemistry, we will analyze each statement provided in the video transcript step by step.

### Step-by-Step Solution:

1. **Identify the Groups of Basic Radicals**:
- Basic radicals are categorized into different groups based on their precipitation reactions with specific reagents.

2. **Evaluate the First Statement**:
- The first statement claims that "the group first basic radicals are precipitated as a chloride."
- This is true. For example, when we use dilute HCl, we can precipitate basic radicals such as AgCl (from Ag+) and PbCl2 (from Pb2+).
- **Conclusion**: This statement is correct.

3. **Evaluate the Second Statement**:
- The second statement claims that "the fourth group of basic radicals are precipitated as a sulphide."
- This is also true. For instance, when we use H2S as a reagent, we can precipitate ZnS (from Zn2+) and NiS (from Ni2+).
- **Conclusion**: This statement is correct.

4. **Evaluate the Third Statement**:
- The third statement claims that "the fifth group is also correct because the precipitates in this are as carbonate."
- This statement is true as well. For example, using NH4H2CO3, we can precipitate BaCO3 (from Ba2+) and SrCO3 (from Sr2+).
- **Conclusion**: This statement is correct.

5. **Final Conclusion**:
- Since all three statements regarding the precipitation of basic radicals are correct, we can conclude that the correct answer is that all the statements provided are true.

### Final Answer:
All of the statements regarding the precipitation of basic radicals are correct.