Answer: Toxic, foul-smelling gas used in semiconductor doping and as a fumigant.
- A Toxic, foul-smelling gas used in semiconductor doping and as a fumigant
- B A sweet-smelling gas commonly used as a food flavouring agent
- C A chemically inert gas that does not react with common oxidisers
- D A dense liquid that condenses readily at room temperature
Correct answer: A. Toxic, foul-smelling gas used in semiconductor doping and as a fumigant
Explanation: Phosphine is a toxic colourless gas (like garlic/decaying fish); used as a dopant source and stored-grain fumigant.
Xenon tetrafluoride (XeF4) has six electron domains around xenon — four Xe–F bonds plus two lone pairs. The lone pairs occupy opposite axial positions, leaving the four fluorine atoms in a square-planar shape (Xe–F ≈ 194 pm). Image: ChemSim, Public Domain, via Wikimedia Commons.
Concept context
Covers the nitrogen family (Group 15), oxygen family (Group 16), halogens (Group 17), and noble gases (Group 18). One of the highest-weightage inorganic chapters in NEET and JEE - includes preparation and properties of HNO₃, H₂SO₄, interhalogens, and xenon compounds.