## Question

### Solution

Correct option is

6

Since, MgO and NaCl (rock salt) structure, and in NaCl the coordination number of ions are 6 and 6 respectively. Thus, in MgO, O2– also have coordination number 6.

#### SIMILAR QUESTIONS

Q1

Match box belongs to

Q2

The anions (A) from hexagonal close packing and atoms (M) occupy only two-third of the octahedral voids. The general formula of the compound is

Q3

In a crystalline solid, having formula AB2O4, oxide ions are arranged in cubic close packed lattice while cations A are present in tetrahedral voids and cations B are present in octahedral voids. The percentage of tetrahedral voids occupied by A is

Q4

Ag metal crystallises in a cubic closest packed arrangement with the edge of the unit cell having a length a = 407 pm. The radius of the similar atom is

Q5

The density of solid argon is 1.65 g/mL at –233oC. If the argon atom is assumed to be sphere of radius 1.54 × 10–8 cm, what percentage of solid argon is apparently empty space?(At wt of Ar = 40).

Q6

A compound CuCl has fcc structure. Its density is 3.4 g cm–3, what is the length of unit cell?

Q7

A metal crystallizes into two cubic phases fcc and bcc whose unit cell lengths are 3.5 and 3.0 Å respectively. What is the ratio of densities of fcc and bcc?

Q8

The radius of a divalent cation M2+ is 94 pm and that of divalent anion X2–is 146 pm. Thus, M2+ X2– has

Q9

If NaCl is doped with 10–3 mol% of SrCl2, calculate the concentration of cation vacancies

Q10

The composition of a sample of wustite is Fe0.93 O. What percentage of the iron is present in the form of  Fe III?