Question

Among the following the correct statements are
I. Germanium exists only in traces
II. PbF4 molecule is tetrahedral in shape
III. GeX2 is more stable than GeX4

• A. II, III only
• B. III, II only
• C. II, I only
• D. I, II only

Hint:

For stability comparisons in chemical compounds, always consider factors like electron pair repulsion and the octet rule.

Answer 1

The Correct Option is A

- Statement I: Germanium does exist in traces, but the question does not make this fact clear enough for this context. - Statement II: PbF\(_4\) is indeed tetrahedral in shape. - Statement III: GeX\(_2\) (such as GeCl\(_2\)) is more stable than GeX\(_4\) due to the lesser electron-electron repulsion in the 2-valent compound compared to the 4-valent one. Thus, the correct statements are II and III.

Answer 2

Step 1: Understanding the Occurrence of Germanium
Statement I says that Germanium exists only in traces. This is true in the sense that Germanium is a rare element found in very small amounts in the Earth's crust. However, this fact does not directly relate to the chemical properties involved in the question.

Step 2: Shape of PbF₄ Molecule
Statement II says PbF₄ molecule is tetrahedral in shape. This is correct because lead (Pb) in PbF₄ has four fluorine atoms bonded symmetrically around it. According to VSEPR theory, four bonded pairs and no lone pairs on Pb result in a tetrahedral geometry.

Step 3: Stability of Germanium Compounds GeX₂ vs GeX₄
Statement III says GeX₂ is more stable than GeX₄. This is correct because Germanium prefers the +2 oxidation state (GeX₂) over the +4 state (GeX₄) due to the inert pair effect. The inert pair effect stabilizes the lower oxidation state, making GeX₂ compounds more stable than GeX₄.

Step 4: Conclusion
Therefore, among the statements, II and III are correct while I is not directly relevant in this context.