Select the incorrect statement.

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) $1$. $F$-centres (Farbe centres) are anionic vacancies occupied by electrons,which impart colour to the crystal. This is a correct statement.$2$.

Vedclass · Accepted Answer

There are four unit cells in tetragonal crystal system.

Vedclass · Answer

(D) $1$. $F$-centres (Farbe centres) are anionic vacancies occupied by electrons,which impart colour to the crystal. This is a correct statement.$2$. Schottky defect involves the loss of equal numbers of cations and anions,maintaining the electrical neutrality and stoichiometry of the crystal. This is a correct statement.$3$. In an orthorhombic crystal system,the axial angles are $\alpha = \beta = \gamma = 90^o$. This is a correct statement.$4$. The tetragonal crystal system consists of only two types of unit cells: primitive (simple) and body-centred. There are not four unit cells. Therefore,this statement is incorrect.

Similar Questions

The unit cell with crystallographic dimensions,$a \neq b \neq c$,$\alpha = \gamma = 90^{\circ}$ and $\beta \neq 90^{\circ}$ is

The number of atoms per unit cell in a primitive cubic unit cell is ........ .

The crystal system following the parameters $a \neq b \neq c$ and $\alpha \neq \beta \neq \gamma \neq 90^\circ$ is ...... .

Out of $7$ crystal systems,how many have face-centered unit cells?

The parameters of the unit cell of a substance are $a=2.5, b=3.0, c=4.0, \alpha=90^{\circ}, \beta=120^{\circ}, \gamma=90^{\circ}$. The crystal system of the substance is :

Vedclass Test Series

Exam Paper Generator

Online Exam Module