Solid Z contains two cations (positive ions) and one anion (negative ion).
One of the cations is Fe3+\text{Fe}^{3+}Fe3+.
The table describes the tests carried out on an aqueous solution of Z and some of the observations made. Complete the table by giving the missing observation.
| Test | Observation |
|---|---|
| Add sodium hydroxide solution | [Missing Observation] |
| Then heat the mixture and test the gas given off with damp red litmus paper | Litmus paper turns blue |
| Add dilute nitric acid, then add a few drops of silver nitrate solution | Yellow precipitate forms |
Which cation, other than Fe3+\text{Fe}^{3+}Fe3+, is present in Z? Explain your answer.
Identify the anion present in Z.
When zinc is added to a solution containing Fe3+\text{Fe}^{3+}Fe3+ ions, a reaction occurs. The ionic equation for this reaction is:
Zn(s)+2Fe3+(aq)→Zn2+(aq)+2Fe2+(aq) \text{Zn(s)} + 2\text{Fe}^{3+}(\text{aq}) \rightarrow \text{Zn}^{2+}(\text{aq}) + 2\text{Fe}^{2+}(\text{aq}) Zn(s)+2Fe3+(aq)→Zn2+(aq)+2Fe2+(aq)Identify the reducing agent in this reaction and explain your choice.
