To determine which of the given compounds are soluble, we can use general solubility rules that are applicable to common chemical compounds. Here's a breakdown of each compound's solubility:
1. Ba(OH)2: Soluble.
2. NaBr: Soluble.
3. AgCl: Insoluble.
4. CaS: Soluble.
5. CaCO3: Insoluble.
6. SrSO4: Insoluble.
7. NH4Br: Soluble.
Given these observations, the compounds that are soluble are:
- Ba(OH)2
- NaBr
- CaS
- NH4Br
Thus, the indices that correspond to these soluble compounds are:
- Ba(OH)2: Index 0
- NaBr: Index 1
- CaS: Index 3
- NH4Br: Index 6
So the indices of the soluble compounds are 0, 1, 3, and 6. Therefore, the soluble compounds are:
1. Ba(OH)2
2. NaBr
3. CaS
4. NH4Br