Question

In group 13 elements, element Y has the lowest boiling point and element Z has lowest melting point. The nature of oxides of Y and Z is respectively:

• A. Acidic, amphoteric
• B. Amphoteric, Basic
• C. Basic, amphoteric
• D. Amphoteric, amphoteric

Hint:

Metallic character increases down the group, so oxides become more basic as atomic number increases.

Answer 1

The Correct Option is C

Step 1: List Group 13 elements.
The group is B, Al, Ga, In, Tl. We need element Y with the lowest boiling point and element Z with the lowest melting point, then the nature of their oxides.
Step 2: Identify Z by melting point.
Gallium has an unusually low melting point (it melts near body temperature), so Z is gallium.
Step 3: Identify Y by boiling point.
Among these elements thallium has the comparatively low boiling point, so Y is thallium.
Step 4: Nature of Y's oxide.
Thallium sits low in the group where metallic character is strongest, so $Tl_2O$ is basic.
Step 5: Nature of Z's oxide.
Gallium oxide $Ga_2O_3$ behaves as amphoteric, reacting with both acids and bases.
Step 6: Combine in the asked order.
Oxides of Y then Z are basic, amphoteric, which is option 3.
\[ \boxed{\text{Basic, amphoteric}} \]