Which of the following metals can displace aluminium from an aluminium sulphate solution?

Correct option is D

Sol: The correct answer is (d) Mg 

Key points:

• Magnesium (Mg) is highly reactive and placed higher in the reactivity series of metals, meaning it is more reactive than many other metals, including aluminium.
• ​Due to its position, magnesium can displace less reactive metals (like aluminium) from their compounds.
  
• Magnesium is capable of displacing metals that are less reactive than itself from their compounds in solutions.
  
• Magnesium reacts with water (at higher temperatures) and dilute acids such as hydrochloric acid (HCl) to release hydrogen gas.
• It is used in flash photography and fireworks due to its ability to burn with a bright, white flame.
• Magnesium is also used in the production of fertilizers, medications (e.g., magnesium sulfate as a laxative), and in lightweight materials for aircraft and automotive industries.​
  

Information booster:

Reactivity Series of Metals:

1. Magnesium (Mg) is the most reactive.
2. Aluminium (Al) comes next, but it is covered by a protective oxide layer, which makes it less reactive in some conditions.
3. Iron (Fe) is less reactive than aluminium.
4. Copper (Cu) and Mercury (Hg) are much less reactive than aluminium.