Question:

$Na$ and $Mg$ crystallise in BCC and FCC type crystals, then the number of $Na$ and $Mg$ atoms present in the unit cell of their respective crystal is

Updated On: Jul 6, 2022

4 and 2
9 and 14
14 and 9
2 and 4

Hide Solution

Verified By Collegedunia

The Correct Option is D

Solution and Explanation

No. of atoms per unit cell in $BCC$ structure $= 2$ No. of atoms per unit cell in $FCC$ structure $= 4$

Was this answer helpful?

Notes on The solid state

Concepts Used:

Solid State

Solids are substances that are featured by a definite shape, volume, and high density. In the solid-state, the composed particles are arranged in several manners. Solid-state, in simple terms, means "no moving parts." Thus solid-state electronic devices are the ones inclusive of solid components that don’t change their position. Solid is a state of matter where the composed particles are arranged close to each other. The composed particles can be either atoms, molecules, or ions.

Types of Solids:

Based on the nature of the order that is present in the arrangement of their constituent particles solids can be divided into two types;

Amorphous solids behave the same as super cool liquids due to the arrangement of constituent particles in short-range order. They are isotropic and have a broad melting point (range is about greater than 5°C).
Crystalline solids have a fixed shape and the constituent particles are arranged in a long-range order.