Reactions between reagents

Question

我係一本書到見到以下既 question, 但係唔識，又無答案，可唔可以教下我?

Please write the relevant equation for the following pairs of reagents if reaction is predictable.

1. sodium iodide solution + bromine water
2. iron(II) nitrate solution + acidified potassium permanganate solution
3. magnesium bromide solution + sulphur dioxide gas
4. acidified potassium dichromate solution + magnesium

最好可以解埋俾我聽．．．

Answer 1

1. sodium iodide solution + bromine water
2I- + Br2 --> 2Br- + I2
這是一個氧化還原反應。

2. iron(II) nitrate solution + acidified potassium permanganate solution
5Fe2+ + MnO4- + 8H+ --> 5Fe3+ + Mn2+ + 4H2O
這是一個氧化還原反應。

3. magnesium bromide solution + sulphur dioxide gas
Mg2+ + S2 + H2O --> MgSO3 + 2H+
因為MgSO3是不溶於水的。

4. acidified potassium dichromate solution + magnesium

2006-11-14 20:56:02 補充：
4. acidified potassium dichromate solution + magnesium Cr2O72- + 14H+ + 3Mg --> 2Cr3+ + 3Mg2+ + 7H2O 這是一個氧化還原反應。