Tag: chemistry

Questions Related to chemistry

Which of the following solid is made up of ions?

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. Sugar

  2. Common salt

  3. Polythene

  4. Wood

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Correct Option: B

Which of the following ionic solids has the lowest melting point?

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. $KCl$

  2. $NaCl$

  3. $LiF$

  4. $LiCl$

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Correct Option: A
Explanation:

Melting point of an ionic compound is determined by the electrostatic attraction between cations and anions. It takes a lot of energy to overcome this attraction to allow the ions to move freely and form a liquid. The factor witch effect melting point is charge of the ion. Since, $KCl$ has $+1$ and $-1$ charge on its' cations and anions respectively. Hence, it has the lowest melting point.


Hence, the correct option is $A$

Statement: An ionic solid has some point defect but its experiment density is equal to its theoretical density.


State whether the given statement is true or false.

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. True

  2. False

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Correct Option: A
Explanation:

An ionic solid has some point defect but its experimental density is equal to its theoretical density. The type of defect is Frenkel effect.

When an ion leaves its correct lattice site and occupies an interstitial site, Frenkel defect is observed. Hence, the density of the crystal is not affected.

In a Schottky defect, the density of the crystal decreases.

Hence, the given statement is $\text{true}$

AB is an ionic solid. The ionic radii of A+ and B- are respectively Rc and Ra. Lattice energy of AB is proportional to

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. Rc/Ra

  2. Rc + Ra

  3. Ra/Rc

  4. 1/(Rc+Ra)

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Correct Option: D

Crystals which are good conductor of electricity  and heat are known as:

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. Ionic crystals

  2. Convalent crystals

  3. Molecular crystals

  4. All the above

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Correct Option: A

Carborundum is a :-

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. molecular solid

  2. covalent solid

  3. ionic solid

  4. amorphous solid

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Correct Option: B

Graphite is a lubricating solids due to 

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. Network structure

  2. Free valence electeons

  3. London forces between layers

  4. Both $(1)$ and $(3)$

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Correct Option: A

The polar molecular soild is: 

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. Naphthlene

  2. Dry ice

  3. Sulphur dioxide

  4. Iodine

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Correct Option: A

Graphite is a :

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. metallic crystal

  2. covalent crystal

  3. ionic crystal

  4. molecular crystal

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Correct Option: B

The lattice of a covalent crystal is composed of :

chemistry solid state classification of crystalline solids classification of solids introduction to solids

  1. atoms

  2. molecules

  3. ions

  4. compounds

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Correct Option: A
Explanation:

A covalent network crystal consists of atoms at the lattice points of the crystal, with each atom being covalently bonded to its nearest neighbour atoms.


The covalently bonded network is three-dimensional and contains a very large number of atoms.

Examples of these crystals include graphite and diamond.
In these crystals, the atoms form covalent bonds with one another.