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In the following questions a statement o...

In the following questions a statement of assertion (A) is followed by a statement of reason ( R)
A : `Na_(2) O` is more basic than `AI_(2) O_(3)` .
R : Sodium is less electropositive than aluminium.

A

If Both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1) .

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion then mark (2)

C

If Assertion is true statement but Reason is false then mark (3)

D

If both Assertion and Reason are false statements then mark (4)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we will analyze both the assertion (A) and the reason (R) provided in the statement. ### Step 1: Analyze the Assertion (A) The assertion states that Na₂O is more basic than Al₂O₃. - **Basicity of Oxides**: The basicity of an oxide is determined by the electropositivity of the metal. More electropositive metals form more basic oxides. - **Sodium Oxide (Na₂O)**: Sodium (Na) is an alkali metal and is highly electropositive. - **Aluminum Oxide (Al₂O₃)**: Aluminum (Al) is a metalloid and is less electropositive than sodium. ### Conclusion from Step 1: Since sodium is more electropositive than aluminum, Na₂O is indeed more basic than Al₂O₃. Thus, the assertion (A) is **true**. ### Step 2: Analyze the Reason (R) The reason states that sodium is less electropositive than aluminum. - **Electropositivity Trend**: In the periodic table, electropositivity increases down a group and decreases across a period from left to right. Sodium is in Group 1, while aluminum is in Group 13. - **Comparison**: Since sodium is in Group 1, it is more electropositive than aluminum, which is in Group 13. ### Conclusion from Step 2: The statement that sodium is less electropositive than aluminum is **false**. ### Final Conclusion: - **Assertion (A)**: True (Na₂O is more basic than Al₂O₃) - **Reason (R)**: False (Sodium is more electropositive than aluminum) ### Answer: The correct option is that the assertion is true, but the reason is false. ---
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