The combining capacity of an element is called valency. The valence electrons determine the combining capacity of an atom. The number of bonds that an atom can form as part of a compound is expressed by the valency of the element. For example- The valency of hydrogen is 1, oxygen is 2, carbon is 4, etc.

If the formula of sulphate of a metalMisM2SO43then the valence of metal Mis

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

The cubic unit cell structure of a compound containing cation $M$ and anion $X$ is shown below. When compared to the anion, the cation has smaller ionic radius. Choose the correct statement(s).

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

The radius of

K^{+}

is

133 pm

and that of

{Cl}^{-}

is

181 pm

. The volume of the unit cell of

KCl

expressed in

10^{- 22} {cm}^{3}

is:

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

The contribution to the total current in a semiconductor, due to electrons and holes are

0.75

and

0.25

respectively. The drift velocity of electrons is

\frac{3}{2}

times that of holes at this temperature. Then the ratio between electron concentration and hole concentration is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

In the following circuit diagram, the current through the battery is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

An element occurring in the

BCC

structure has

12.05 \times 10^{23}

unit cells. The total number of atoms of the element in these cells will be

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Among the following, which have highest melting point?

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

The barrier potential of a p-n junction depends on:

(a)

type of semi-conductor material

(b)

amount of doping

(c)

temperature
Which one of the following is correct?

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Match the following

List - I List-II
A) Metallic solid I) Carbon tetrachloride
B) Covalent solid II) Calcium fluoride
C) Molecular solid III) Copper
D) Ionic solid IV) Silicon carbide
V) Glass

The correct answer is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Consider an ionic solid

MX

, with

NaCl

structure. Construct a new structure

(Z)

, whose unit cell is constructed from the unit cell of

MX

, following the sequential instructions given below. Neglect the charge balance.

(i)

Remove all the anions

(X)

, except the central one.

(ii)

Replace all the face centered cations

(M)

, by anions

(X)

.

(iii)

Remove all the corner cations

(M)

.

(iv)

Replace the central anion

(X)

, with cation

(M)

.

The value of

(\frac{n u m b e r o f a n i o n s}{n u m b e r o f c a t i o n s})

in

Z

is _____.

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

In calcium fluoride, having the fluorite structure, the coordination numbers for calcium ion

(C a^{2 +})

and fluoride ion

(F^{-})

are

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Glass is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Valence electron in

{Cl}^{-}

ions is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Silicon doped with gallium forms

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

An intrinsic semiconductor is converted into

n

-type extrinsic semiconductor by doping it with:-

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Which among the following is NOT a polar molecular solid ?

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Which of the following oxides shows electrical properties like metals?

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

A compound formed by elements

X

and

Y

crystallises in the cubic structure, where

X

atoms are at the corners of a cube and

Y

atoms are at the centre of the body. The formula of the compounds is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

A unit cell of calcium fluoride has four calcium ions. The number of fluoride ions in the unit cell is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

The pair of valencies exhibited by tin

(Sn)

is

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Physical Sciences>Matter and Its Interactions>Develop models to describe the atomic composition of simple molecules and extended structures.>Structure and Properties of Matter - Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Define valency.

If the formula of sulphate of a metal $M$ is $M_{2} {({SO}_{4})}_{3}$ then the valence of metal $M$ is

Important Questions on Develop models to describe the atomic composition of simple molecules and extended structures.

Learn and Prepare for any exam you want !

If the formula of sulphate of a metal M is M2SO43 then the valence of metal M is

Important Questions on Develop models to describe the atomic composition of simple molecules and extended structures.

Learn and Prepare for any exam you want !

If the formula of sulphate of a metal $M$ is $M_{2} {({SO}_{4})}_{3}$ then the valence of metal $M$ is