🧪 Chemistry · p-Block Elements (Groups 15 to 18) · NEET & JEE

Laughing gas, used as a mild anaesthetic, is:

Answer: N₂O.

A NO
B N₂O
C NO₂
D N₂O₃

Correct answer: B. N₂O

Explanation: Dinitrogen oxide (nitrous oxide), N₂O, is a colourless gas used as a mild anaesthetic and is commonly called laughing gas.

Xenon tetrafluoride XeF4: a central xenon bonded to four fluorine atoms in a square-planar arrangement with two lone pairs above and below, Xe-F bond length 194 pm.

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.

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Laughing gas, used as a mild anaesthetic, is:

Concept context

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