JEE Main 2020 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 3 September 2020, Shift 1, Chemistry Q47

Question 47 of 75 in this shift, Chemistry question 22 of 25.

An element with molar mass

2.7\times10^{-2}

\mathrm{kg\ mol^{-1}}

forms a cubic unit cell with edge length 405 pm. If its density is

2.7\times10^{3}

\mathrm{kg\ m^{-3}}

, the radius of the element is approximately __________

\times10^{-12}

m (to the nearest integer).

Official answer

143.00

NTA final key (Sep 2020).

Chapter: The Solid State
Topic: Crystal Lattices
Idea tested: Unit Cell Density

Same idea in other shifts

Asked 9× in all

11 Apr 2023, Shift 1 · Q82An atomic substance A of molar mass $12\ \mathrm{g\ mol^{-1}}$ has a cubic crystal structure with edge length of 300 pm. The no. of atoms…MediumNumerical value
28 Jul 2022, Shift 1 · Q82An element M crystallises in a body centred cubic unit cell with a cell edge of 300 pm. The density of the element is…MediumNumerical value
28 Jul 2022, Shift 2 · Q52Metal M crystallizes into a fcc lattice with the edge length of $4.0\times10^{-8}$ cm. The atomic mass of the metal is ______ g/mol.…EasyNumerical value
25 Jun 2022, Shift 1 · Q82The distance between $\mathrm{Na^+}$ and $\mathrm{Cl^-}$ ions in solid NaCl of density $43.1\ \mathrm{g\ cm^{-3}}$ is __________…MediumNumerical value
30 Jun 2022, Shift 1 · Q61An element X has a body centred cubic (bcc) structure with a cell edge of 200 pm. The density of the element is 5 g cm $^{-3}$ . The number…MediumSingle correct
25 Feb 2021, Shift 2 · Q52The unit cell of copper corresponds to a face centered cube of edge length 3.596 Å with one copper atom at each lattice point. The…MediumNumerical value
22 Jul 2021, Shift 2 · Q52A copper complex crystallising in a CCP lattice with a cell edge of 0.4518 nm has been revealed by employing X-ray diffraction studies.…MediumNumerical value
5 Sep 2020, Shift 1 · Q40A diatomic molecule $\mathrm{X_2}$ has a body-centred cubic (bcc) structure with a cell edge of 300 pm. The density of the molecule is…MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.