Given: Two statements are to be checked. Statement I concerns the nature of Group 14 oxides, and Statement II concerns the properties of BF3.
Find: Which option correctly describes the truth values of Statement I and Statement II.
For Statement I, examine each pair:
- [SiO2, CO2]: both are acidic oxides, so this pair does not qualify.
- [SnO, SnO2]: both are amphoteric oxides, so this pair qualifies.
- [PbO, PbO2]: both are amphoteric oxides, so this pair qualifies.
- [GeO, GeO2]: GeO2 is amphoteric, but GeO is not typically classified as amphoteric, so this pair does not qualify.
Thus, the number of pairs in which both oxides are amphoteric is exactly 2. Therefore, Statement I is true.
For Statement II:
- BF3 is electron deficient because boron has only six electrons around it.
- Therefore, BF3 can act as a Lewis acid.
- It forms an adduct with NH3 as F3B←NH3.
- With three bond pairs and no lone pair on boron, its geometry is trigonal planar.
Hence, Statement II is true.
Therefore, both Statement I and Statement II are true. The correct option is C.