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प्रश्न
Answer the following in brief.
Distinguish between ionic solids and molecular solids
उत्तर
| Ionic solids | Molecular solids |
| 1. The constituent particles are charged ions (cations and anions). | 1. The constituent particles are monoatomic or polyatomic molecules |
| 2. The constituent particles are held by the electrostatic force of attraction between oppositely charged ions. | 2. The constituent particles are held by intermolecular forces of attractions such as London forces, dipole-dipole forces and/or hydrogen bonds. |
| 3. They are hard and brittle. | 3. They are soft. |
| 4. They have high melting points. | 4. They have low melting points. |
| 5. They are nonconductors of electricity in solid-state. However, they are good conductors when melted or dissolved in water. | 5. They are poor conductors of electricity. |
| 6. e.g. NaCl, CaF2, etc. | 6. Ice, benzoic acid, etc. |
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संबंधित प्रश्न
Ionic solids conduct electricity in molten state but not in solid state. Explain
Explain Ionic solids are hard and brittle.
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a. Ammonium phosphate
b. Brass
c. S8 molecule
d. Diamond
Define Anisotropy.
Account for the following :
o-nitrophenol is more steam volatile than p-nitrophenol.
Answer the following in one or two sentences.
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Classify the following solid.
P4
Classify the following solid.
Diamond
Classify the following solid.
Iodine
Select the INCORRECT match:
Which of the following is an example of molecular solid?
____________ is an example of molecular crystal.
Dry ice is an example of ____________.
Brass is an example of ____________.
Solid X is a very hard electrical insulator in solid as well as in molten state. It melts at extremely high temperature. Solid X is a ____________.
Nature of binding forces present in carbon dioxide molecules in solid state are ____________.
Ionization enthalpy is lowest in ____________.
London forces are present in ____________.
MgO has the structure of NaCl. The coordination number of the ions in MgO is ____________.
The compound, found in nature in gas phase but ionic in solid state is ____________.
Solid CH4 is ____________.
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The major binding force of diamond, silicon and quartz is ____________.
In graphite electrons are ____________.
Which of the following is a network solid?
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(i) SiC (Silicon carbide)
(ii) AlN
(iii) Diamond
(iv) I2
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(i) some of the anionic sites are occupied by an unpaired electron.
(ii) some of the anionic sites are occupied by a pair of electrons.
(iii) there are vacancies at some anionic sites.
(iv) F-centres are created which impart colour to the crystals.
Why are liquids and gases categorised as fluids?
Inspite of long range order in the arrangement of particles why are the crystals usually not perfect?
A crystal with a ≠ b ≠ c and α = β = γ = 90° is
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Which of the following is not correct?
Mention the res of the following solid:
CO2
