NEET UG 2018 · Chemistry · Question 89

NEET 2018 Chemistry, question 89

Question 89 of the NEET 2018 paper (code AA) is a Chemistry question from The Solid State. Its idea, Density of a Unit Cell, was asked twice, in 2018 and 2022, across NEET 2017–2026. The CBSE official answer key gives option 1.

Updated 2026-10-08

Q89 · Chemistry

Iron exhibits bcc structure at room temperature. Above 900°C, it transforms to fcc structure. The ratio of density of iron at room temperature to that at 900°C (assuming molar mass and atomic radii of iron remains constant with temperature) is

\frac{3\sqrt{3}}{4\sqrt{2}}

Official answer: option 1 · CBSE official answer key

Same idea

Density of a Unit Cell, in other papers

NEET asked this idea twice, in 2018 and 2022. The other question below.

3.608\times10^{-8}

Density of a Unit Cell: every question and how it was framed

The chapter

The Solid State in ten years of NEET

10 questions from 2017–2026, asked in 7 of 10 papers, about 0.9 a paper. The Solid State alone had 10.

Chapter analysis

Density of a Unit Cell, in other papers

The Solid State in ten years of NEET

The Solid State: questions per paper