1
JEE Main 2023 (Online) 1st February Evening Shift
Numerical
+4
-1

A metal M crystallizes into two lattices :- face centred cubic (fcc) and body centred cubic (bcc) with unit cell edge length of $$2.0$$ and $$2.5\,\mathop A\limits^o$$ respectively. The ratio of densities of lattices fcc to bcc for the metal M is ____________. (Nearest integer)

2
JEE Main 2023 (Online) 30th January Evening Shift
Numerical
+4
-1
Iron oxide FeO, crystallises in a cubic lattice with a unit cell edge length of 5.0 Å. If density of the $\mathrm{FeO}$ in the crystal is $4.0 \mathrm{~g} \mathrm{~cm}^{-3}$, then the number of $\mathrm{FeO}$ units present per unit cell is __________. (Nearest integer)

Given: Molar mass of $\mathrm{Fe}$ and $\mathrm{O}$ is 56 and $16 \mathrm{~g} \mathrm{~mol}^{-1}$ respectively. $\mathrm{N}_{\mathrm{A}}=6.0 \times 10^{23} \mathrm{~mol}^{-1}$
3
JEE Main 2023 (Online) 29th January Evening Shift
Numerical
+4
-1

A metal M forms hexagonal close-packed structure. The total number of voids in 0.02 mol of it is _________ $$\times$$ $$10^{21}$$ (Nearest integer).

(Given $$\mathrm{N_A=6.02\times10^{23}}$$)

4
JEE Main 2022 (Online) 29th July Morning Shift
Numerical
+4
-1

Ionic radii of cation $$\mathrm{A}^{+}$$ and anion $$\mathrm{B}^{-}$$ are 102 and $$181 \,\mathrm{pm}$$ respectively. These ions are allowed to crystallize into an ionic solid. This crystal has cubic close packing for $$\mathrm{B}^{-}$$. $$\mathrm{A}^{+}$$ is present in all octahedral voids. The edge length of the unit cell of the crystal AB is __________ pm. (Nearest Integer)

JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Mathematics
Algebra
Trigonometry
Coordinate Geometry
Calculus
EXAM MAP
Joint Entrance Examination
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Medical
NEET