Sodium thiosulphate reacts with which of the following to convert into complex thiosulphates
A) ferric chloride
B) auric chloride
C) cupric chloride
The correct option is 

Options

A. B only
B. A and C
C. A and B
D. A, B and C

Answer

To determine which of the given compounds (ferric chloride, auric chloride, or cupric chloride) reacts with sodium thiosulfate to form complex thiosulfates, we will analyze each option step by step.

### Step 1: Understanding Sodium Thiosulfate
Sodium thiosulfate has the chemical formula \( \text{Na}_2\text{S}_2\text{O}_3 \). It is known to form complexes with certain metal ions.

### Step 2: Reaction with Ferric Chloride
- **Chemical Formula**: Ferric chloride is \( \text{FeCl}_3 \).
- **Reaction**:
\[ \text{Na}_2\text{S}_2\text{O}_3 + \text{FeCl}_3 \rightarrow \text{Fe}_2(\text{S}_2\text{O}_3) + \text{NaCl} \]
- **Complex Formation**: The product is a complex thiosulfate of iron, specifically ferric thiosulfate.

### Step 3: Reaction with Auric Chloride
- **Chemical Formula**: Auric chloride is \( \text{AuCl}_3 \).
- **Reaction**:
\[ \text{Na}_2\text{S}_2\text{O}_3 + \text{AuCl}_3 \rightarrow \text{Au}(\text{S}_2\text{O}_3) + \text{NaCl} \]
- **Complex Formation**: The product is a complex thiosulfate of gold, specifically auric thiosulfate.

### Step 4: Reaction with Cupric Chloride
- **Chemical Formula**: Cupric chloride is \( \text{CuCl}_2 \).
- **Reaction**:
\[ \text{Na}_2\text{S}_2\text{O}_3 + \text{CuCl}_2 \rightarrow \text{Cu}(\text{S}_2\text{O}_3) + \text{NaCl} \]
- **Complex Formation**: The product is a complex thiosulfate of copper, specifically cupric thiosulfate.

### Conclusion
All three reactions show that sodium thiosulfate reacts with ferric chloride, auric chloride, and cupric chloride to form complex thiosulfates. Therefore, the correct answer is:

**Correct Option: All of the above (A, B, and C)**