In corrundum, oxid ions are arranged in ...

In corrundum, oxid ions are arranged in `h.c.p.` array and the aluminum ions occupy two`-`thirds of octahedral voids. What is the formula of currundum ?

Text Solution

Verified by Experts

Number of oxides per unit cell = 6
Number of octahedral voids per unit cell = 6
Number of `Al^(+3)` ions in octahedral voids `= (6xx2)/(3)=4`
`therefore Al^(+3):O^(-2)`
4 : 6 or 2 : 3
Hence, formula is `Al_(2)O_(3)`.

Topper's Solved these Questions

THE SOLID STATE
AAKASH INSTITUTE|Exercise ASSIGNMENT SECTION-A (OBJECTIVE)|50 Videos
THE SOLID STATE
AAKASH INSTITUTE|Exercise ASSIGNMENT SECTION-B (OBJECTIVE)|27 Videos
THE SOLID STATE
AAKASH INSTITUTE|Exercise Assignment (SECTION - D) (ASSERTION-REASON TYPE QUESTION)|20 Videos
THE S-BLOCK ELEMENTS
AAKASH INSTITUTE|Exercise Assignment (Section-J)|10 Videos
THERMODYNAMICS
AAKASH INSTITUTE|Exercise ASSIGNMENT (Section -D) Assertion-Reason Type Questions|15 Videos

Similar Questions

Explore conceptually related problems

(i) In corundum, oxide ions are arranged in hexagonal close packing and aluminium ions occupy two third of octahedral voids. What is the formula of corundum ? (ii) The unit cell of silver iodide (Agl) has 4 iodine atoms in it. How many silver atoms must be there in the unit cell ?

In corundum, oxide ions are arranged in hexagonal close packing and aluminium ionsa occpy tow-third of the octaheral voids. What is the formula of corrundum ? .

In sapphire, oxide ions are arranged in hexagonal close packing and aluminium ions occupy two-thirds of the octahedral voids. What is the formula of sapphire?

In a metal oxide , the oxide ions are arranged in hexagonal close packing and metal lone occupy two - third of the ocishedral voids .The formula of the oxide is

In a crystalline solid, anions B arranged in ccp lattice and cations A occupy 50% of the octahedral voids. And 50% of the tetrahedral voids. What is the formula of the solid?

AAKASH INSTITUTE-THE SOLID STATE -Try Yourself

Three atoms P, Q & R crystallize in a cubic solid lattice having P ato...
Text Solution
|
Calculate the approximate number of unit cells present in 1 g of gold....
Text Solution
|
Elements A and B crystallize in cubic structure where atoms A are at t...
Text Solution
|
Three elements P, Q and R crystallise in a cubic solid lattice with P ...
Text Solution
|
In corrundum, oxid ions are arranged in h.c.p. array and the aluminum ...
Text Solution
|
In a compound atoms of element Y form ccp lattice and those of elemen...
Text Solution
|
In a crystalline solid, anions Y are arranged in ccp arrangement. Cati...
Text Solution
|
Calculate the number of atoms in a cubic based unit cell having one at...
Text Solution
|
A compound formed by elements A and B has a cubic structure in which A...
Text Solution
|
The radius of Na(+) is 95 pm and that of CI^(-)ions is 181 pm. Predict...
Text Solution
|
If the radius of Br^(-) ion is 0.182 nn, how large can a cation be fit...
Text Solution
|
A compound AB crystallizes in bcc lattice with unit edge length of 380...
Text Solution
|
Tungsten has bcc lattice. Each edge of unit cell is 316 pm and density...
Text Solution
|
The element chromium crystallises in a body centred cubic lattice whos...
Text Solution
|
Formula mass of NaCl is 58.45g mol^(-1) and density of its pure form i...
Text Solution
|
An element occurs in bcc structure with edge length of 288 pm. Its den...
Text Solution
|
Thallium chloride TlCl crystallises in either a simple cubic lattice o...
Text Solution
|
An element with atomic mass 60 having fcc structure has a density of 6...
Text Solution
|
Analysis shows that a metal oxide has empirical formula M(0.98)O(1.00)...
Text Solution
|
Analysis shows that nickel oxide has the formula Ni(0.98)O(1.00). What...
Text Solution
|