Hypo gives (a) ____ppt. with `AgNO_(3)` which changes to (b) ____.

Answer

To solve the question regarding the reaction of hypo (sodium thiosulphate) with silver nitrate, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- Hypo refers to sodium thiosulphate, which has the chemical formula Na₂S₂O₃.
- The other reactant is silver nitrate, which has the chemical formula AgNO₃.

2. **Write the Reaction**:
- When sodium thiosulphate reacts with silver nitrate, the reaction can be represented as follows:
\[ Na_2S_2O_3 + 2AgNO_3 \rightarrow Ag_2S_2O_3 \downarrow + 2NaNO_3 \]
- Here, Ag₂S₂O₃ (silver thiosulphate) is formed as a precipitate.

3. **Identify the Precipitate**:
- The precipitate formed in the reaction is silver thiosulphate (Ag₂S₂O₃), which is a white precipitate.

4. **Further Reaction of the Precipitate**:
- The white precipitate (Ag₂S₂O₃) can further react in the presence of water:
\[ Ag_2S_2O_3 + H_2O \rightarrow Ag_2S \downarrow + H_2SO_4 \]
- In this reaction, silver sulfide (Ag₂S) is formed, which is a black precipitate.

5. **Final Answers**:
- (a) The first blank is filled with **white precipitate**.
- (b) The second blank is filled with **black precipitate**.

### Final Answer:
Hypo gives (a) **white ppt.** with AgNO₃ which changes to (b) **black ppt.**.