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प्रश्न
Explain ionic solids are hard and brittle.
Ionic solids are hard and brittle. Explain
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उत्तर
- Ionic solids are brittle and rigid.
- The strong electrostatic forces of attraction between the oppositely charged ions, which hold the particles firmly together, are the cause of the hardness.
- Ionic solids are fragile because layers of ions shift when a force is applied.
- Similarly charged ions come opposite each other and repel when a force is applied, causing the layers to slide over one another. The crystal is broken as a result.
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संबंधित प्रश्न
Give an example each of a molecular solid and an ionic solid.
Ionic solids conduct electricity in molten state but not in solid state. Explain
Explain the basis of similarities between metallic and ionic crystals.
An ionic compound crystallises in FCC type structure with ‘A’ ions at the centre of each face and ‘B’ ions occupying corners of the cube. The formula of compound is _______.
Classify the following solids into different types:
a. Ammonium phosphate
b. Brass
c. S8 molecule
d. Diamond
Distinguish between crystalline solids and amorsphous solids.
Classify the following molecular solids into different types:
- HCl
- CO2
- Solid ice
- SO2
Define Anisotropy.
Account for the following :
o-nitrophenol is more steam volatile than p-nitrophenol.
Answer the following in one or two sentences.
A solid is hard, brittle and electrically nonconductor. Its melt conducts electricity. What type of solid is it?
Answer the following in brief.
Distinguish between ionic solids and molecular solids
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Classify the following solid:
Pb
Graphite and diamond are ____________.
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Solid CO2 is an example of ____________.
Assertion: monoclinic sulphur is an example of a monoclinic crystal system
Reason: for a monoclinic system, a ≠ b ≠ c and α = γ = 90°, β ≠ 90°
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Give any three characteristics of ionic crystals.
Classify the following solid.
P4
Classify the following solid.
Brass
Classify the following solid.
Diamond
Classify the following solid.
NaCl
Classify the following solid.
Iodine
If NaCl is doped with 10−2 mol percentage of strontium chloride, what is the concentration of cation vacancy?
Select the INCORRECT match:
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Which of the following is TRUE about molecular solids?
Fullerene is an example of ____________.
Which among the following is NOT a polar molecular solid?
Which among the following is an example of network solid?
Brass is an example of ____________.
Ionization enthalpy is lowest in ____________.
Which among the following is an example of non-polar molecule?
Silicon carbide is an example of ____________.
Among solids, the highest melting point is exhibited by ____________.
The major binding force of diamond, silicon and quartz is ____________.
Which one of the following forms a molecular solid when solidified?
Which of the following is a network solid?
Iodine molecules are held in the crystals lattice by ______.
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An excess of potassium ions makes KCl crystals appear violet or lilac in colour since:
(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.
Which of the following cannot be regarded as molecular solid?
(i) SiC (Silicon carbide)
(ii) AlN
(iii) Diamond
(iv) I2
Why are liquids and gases categorised as fluids?
Who introduced the term covalent bond?
The covalent bond length is the shortest in which one of the following bonds?
Calculate the angle at which first order reflection will occurs in an X-ray spectrometer when x ~ rays of wavelength \[\ce{1.54 \overset{\circ}{A}}\] are diffracted by the atoms of a crystal given that inter planer distance is \[\ce{0.04 \overset{\circ}{A}}\]
The major binding force in diamond, silicon and quartz is ______.
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Among the following which is the best description of water in the solid phase?
Which of the following is not correct?
Graphite is a ______.
Mention the res of the following solid:
Ice
Mention the res of the following solid:
CO2
What are intermolecular forces of attraction involved in molecular crystals?
