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

When copper reacts with dilute nitric acid, the main nitrogen-containing gas evolved is:

Answer: NO.

A NO
B NO₂
C N₂O
D N₂O₅

Correct answer: A. NO

Explanation: Dilute HNO₃ oxidises copper giving nitric oxide: 3Cu + 8HNO₃ gives 3Cu(NO₃)₂ + 2NO + 4H₂O; concentrated acid would give NO₂ instead.

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.

Read the full p-Block Elements (Groups 15 to 18) notes →

When copper reacts with dilute nitric acid, the main nitrogen-containing gas evolved is:

Concept context

More p-Block Elements (Groups 15 to 18) questions