Question

The amphoteric hydroxide is :

• A. $\ce{Ca(OH)2}$
• B. $\ce{Be(OH)2}$
• C. $\ce{Sr(OH)2}$
• D. $\ce{Mg(OH)2}$

Answer 1

The Correct Option is B

To determine which hydroxide is amphoteric, we need to understand what amphoteric substances are. An amphoteric hydroxide is one that can act as both an acid and a base. In other words, it can react with both acids and bases.

1. Understanding Each Option:
   • $\ce{Ca(OH)2}$: Calcium hydroxide is a strong base and typically does not exhibit amphoteric properties.
   • $\ce{Be(OH)2}$: Beryllium hydroxide is known to be amphoteric because it can react with acids to form salts and with bases to form complex beryllate ions.
   • $\ce{Sr(OH)2}$: Strontium hydroxide is similar to other group 2 hydroxides like calcium hydroxide, behaving as a strong base rather than an amphoteric compound.
   • $\ce{Mg(OH)2}$: Magnesium hydroxide, while somewhat less reactive than calcium hydroxide, primarily acts as a base.
2. Conclusion: From the explanations above, $\ce{Be(OH)2}$ is the compound that fits the definition of an amphoteric hydroxide, as it has the ability to react with both acids and bases.

Therefore, the correct answer is $\ce{Be(OH)2}$.