KEAM 2015 Physics and Chemistry Paper

Density of crystal lattice is directly proportional to molar mass and inversely proportional to edge length. d∝‌

M

a3

. If density and molar mass of isomorphous crystal (A) are dA and MA, density and molar mass of isomorphous crystal (B) are dB and MB respectively.
then, ‌

dA

dB

=‌

MA

MB

×(‌

aB

aA

)3
Given, ‌‌MA=?,MB=200g∕mol
‌

dA

dB

=1.6,‌

aB

aA

=2
mA=‌

1.6×200

8

=40g∕mol