To determine which aqueous ionic solutions will react with manganese (Mn) at room temperature, we need to consider the type of reaction that might occur. Specifically, we should examine possible single replacement (displacement) reactions, where a more reactive metal displaces a less reactive metal from its compound in solution.
The reactivity series is a helpful guideline for predicting such reactions. Metals higher in the reactivity series will typically displace metals that are lower in the series from their compounds. Here is a simplified version of the reactivity series for context:
- Potassium (K)
- Sodium (Na)
- Calcium (Ca)
- Magnesium (Mg)
- Aluminum (Al)
- Zinc (Zn)
- Iron (Fe)
- Nickel (Ni)
- Tin (Sn)
- Lead (Pb)
- (Hydrogen)
- Copper (Cu)
- Silver (Ag)
- Gold (Au)
Manganese (Mn) sits between aluminum and zinc in the reactivity series.
To determine which ionic solutions will react with Mn(s):
1. AuCl(aq) (Gold(I) chloride)
- Gold is less reactive than manganese. Thus, manganese can displace gold from its compound.
- Reaction: Mn(s) + AuCl(aq) → MnCl2(aq) + Au(s)
- Conclusion: Reacts
2. ZnCl2(aq) (Zinc chloride)
- Zinc is more reactive than manganese. Manganese cannot displace zinc.
- Reaction: No reaction.
- Conclusion: Does not react
3. NiCl2(aq) (Nickel(II) chloride)
- Nickel is less reactive than manganese. Thus, manganese can displace nickel from its compound.
- Reaction: Mn(s) + NiCl2(aq) → MnCl2(aq) + Ni(s)
- Conclusion: Reacts
4. CaCl2(aq) (Calcium chloride)
- Calcium is more reactive than manganese. Manganese cannot displace calcium.
- Reaction: No reaction.
- Conclusion: Does not react
5. MgCl2(aq) (Magnesium chloride)
- Magnesium is more reactive than manganese. Manganese cannot displace magnesium.
- Reaction: No reaction.
- Conclusion: Does not react
6. AlCl3(aq) (Aluminum chloride)
- Aluminum is more reactive than manganese. Manganese cannot displace aluminum.
- Reaction: No reaction.
- Conclusion: Does not react
7. FeCl3(aq) (Iron(III) chloride)
- Iron is less reactive than manganese. Thus, manganese can displace iron from its compound.
- Reaction: Mn(s) + FeCl3(aq) → MnCl2(aq) + Fe(s)
- Conclusion: Reacts
Based on the reactivity series and the possible reactions, the aqueous ionic solutions that will react with Mn(s) at room temperature are:
- AuCl(aq)
- NiCl2(aq)
- FeCl3(aq)
