Anomalous Behaviour Of Beryllium

Step 1: Diagonal relationship. Be and Al show diagonal relationship in periodic table.
Step 2: Similar properties. Both form covalent compounds and amphoteric oxides.
Step 3: Point of difference. Maximum covalency differs due to size and availability of orbitals.

Step 1: Basic strength.
The basic strength of oxides increases as we move down the group. Thus, the correct order of basic strength is .
Thus, the correct answer is (1).

Step 1: Correct flame colours: Ca → Brick red, Sr → Crimson, Ba → Apple green
Step 2: Thus Calcium and Barium are incorrectly matched.

Step 1: Be and Al show diagonal relationship.
Step 2: Be is not rendered passive by nitric acid unlike aluminium.

Step 1: Understanding the Concept
Quicklime and slaked lime are common names for specific compounds of alkaline earth metals (Group 2 of the s-block). The formulas MO and M(OH) indicate that the metal M has a valency of +2.

Step 2: Detailed Explanation
1. Quicklime: This is the common name for Calcium Oxide ( ). It is produced by the thermal decomposition of limestone ( ). 2. Slaked Lime: When quicklime is treated with water, it undergoes a highly exothermic reaction to form Calcium Hydroxide ( ), which is known as slaked lime. 3. Other Options: - Sodium and Potassium are Group 1 metals (valency +1). - Magnesium Oxide is called Magnesia, not quicklime.

Step 3: Final Answer
The metal M is Calcium.