Sometimes no precipitate is obtained even if group V radicals are present why ?

Explanation

### Step-by-Step Solution:

1. **Understanding Group V Cations**:
- Group V cations include barium (Ba²⁺), calcium (Ca²⁺), and strontium (Sr²⁺). These cations are usually precipitated as their carbonates when treated with the appropriate group reagent.

2. **Group Reagent**:
- The group reagent for Group V cations is ammonium carbonate \((NH_4)_2CO_3\). This reagent is used in the presence of ammonium hydroxide \((NH_4OH)\) and ammonium chloride \((NH_4Cl)\) to facilitate the precipitation of the cations as their respective carbonates.

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