Home
Class 12
CHEMISTRY
The crystal AB(rock salt structure) has ...

The crystal `AB`(rock salt structure) has molecular weight `6.023Y u`, where `Y` is an arbitrary number in `u`. If the minimum distance between cation and anion is `Y^(1)/(3) nm` and the observed density is `20 kg m^(-3)`. Find
a. The density in `kg m^(-3)`. and
b. The type of defect

Text Solution

Verified by Experts

a. Density, `rho = (Z_(eff) xx Mw)/(a^(3) xx N_(A))`
Edge length
`a = 2Y^(1)//(3) xx 10^(-9) m`
For rock salt structure, `Z_(eff) = 4`
`M = 6.023 Y u = (6.023)/(1000) Y kg`
Density, `rho`
`(4 xx (6.023)/(1000) xx10^(-3) xx Y)/(6.023 xx 10^(23) xx (2Y^(1//3) xx 10^(-9))^(3))`
`= (40)/(8) = 5 kg m^(-3)`
b. Observed density `= 20 kg m^(-3)`
Calculated density `= 5 kg m^(-3)`
The observed density is higher than the calculated density, hence, the solid must have non-stoichiometric defect.
Promotional Banner

Topper's Solved these Questions

  • SOLID STATE

    CENGAGE CHEMISTRY|Exercise Ex 1.1 (Subjective)|12 Videos

  • SOLID STATE

    CENGAGE CHEMISTRY|Exercise Ex 1.1 (Objective)|19 Videos

  • SOLID STATE

    CENGAGE CHEMISTRY|Exercise Exercises (Archives ) Interger|1 Videos

  • REDUCTION AND OXIDATION REACTION OF ORGANIC COMPOUNDS

    CENGAGE CHEMISTRY|Exercise SUBJECTIVE TYPE|3 Videos

  • SOLUTIONS

    CENGAGE CHEMISTRY|Exercise Ex 2.3 (Objective)|9 Videos

Similar Questions

Explore conceptually related problems

The crystal AB (rock salt structure) has molecular weight 6.023 y u, where y is an arbitrary number in u. If the minimum distance between cation and anion is y^(1//2) nm and the observed density is 20kg/ m^(3) , find the (i) density in kg/ m^(3) and (ii) type of defect.

AB crystallizes in a rock salt structure. The nearest distance between A and B is Y^(1//3) nm, where Y is a constant. The molecular mass of AB is "6.023 Y g/mol"^(-1) .Determine the density in kgm^(-3) .

A compount AB has a rock type structure with A:B=1:1 . The formula weight of AB is 6.023 Y am u and the closed A-B distance is Y^(1//3) nm. (i) Find the density of lattice. (ii) If the density of lattice is found to be 20 kg m^(-3) , then predict the type of defect.

A compound AB has a rock salt type structure with A:B=1:1 . The formula weight of AB is 6.023 y amu and the closest A-B distance is y^(1//3) nm. Calculate the density of lattice (in kg//m^(3))

For aluminium , the modulus of rigidity is 2.1xx10^(10)Nm^(-2 and density is 2.7xx10^(3)kg//m^(3) .Find the speed of transverse waves in the medium.