Class 12 Chemistry - Chapter The Solid State NCERT Solutions | In terms of band theory, what is the dif
In terms of band theory, what is the difference
(i) Between a conductor and an insulator
(ii) Between a conductor and a semiconductor
(i) In a conductor the energy gap is either very small or there is overlapping between valence band and conduction band. In case of an insulator the energy gap between valence band and conduction band is very large. Due to which, when an electric field is applied to an insulator, the electrons cannot jump from valence band to conduction band, hence poor or no conduction of electricity.
(ii) In a conductor, the energy gap between valence band and conduction band is very small but in an semiconductor there is always a small energy gap between them.
More Questions From Class 12 Chemistry - Chapter The Solid State
- Q:-
If NaCl is doped with 10-3mol % of SrCl2, what is the concentration of cation vacancies?
- Q:-
A cubic solid is made of two elements P and Q. Atoms of Q are at the corners of the cube and P at the body-centre. What is the formula of the compound? What are the coordination numbers of P and Q?
- Q:-
An element with molar mass 2.7 x 10-2kg mol-1 forms a cubic unit cell with edge length 405 pm. If its density is 2.7 x 103 kg m-3, what is the nature of the cubic unit cell?
- Q:-
Copper crystallises into a fcc lattice with edge length 3.61 x 10-8cm. Show that the calculated density is in agreement with its measured value of 8.92 g cm-3.
- Q:-
A compound is formed by two elements M and N. The element N forms ccp and atoms of M occupy 1/3rd of tetrahedral voids. What is the formula of the compound?
- Q:-
Aluminium crystallises in a cubic close-packed structure. Its metallic radius is 125 pm.
(i) What is the length of the side of the unit cell?
(ii) How many unit cells are there in 1.00 cm3of aluminium?
- Q:-
Analysis shows that nickel oxide has the formula Ni0.98 O1.00. What fractions of nickel exist as Ni2+and Ni3+ions?
- Q:-
Distinguish between
(i)Hexagonal and monoclinic unit cells
(ii) Face-centred and end-centred unit cells.
- Q:-
Solid A is a very hard electrical insulator in solid as well as in molten state and melts at extremely high temperature. What type of solid is it?
- Q:-
Ionic solids, which have anionic vacancies due to metal excess defect, develop colour. Explain with the help of a suitable example.
Popular Questions of Class 12 Chemistry
- Q:-
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
- Q:-
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
- Q:-
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
- Q:-
Write any two characteristics of Chemisorption.
- Q:-
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
- Q:-
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
- Q:-
Why are pentahalides more covalent than trihalides?
- Q:-
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
- Q:-
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
- Q:-
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
Recently Viewed Questions of Class 12 Chemistry
- Q:-
Complete each synthesis by giving missing starting material, reagent or products
(i)
(ii)
(iii)
(iv)
(v)
(vi)
- Q:-
The conductivity of 0.20 M solution of KCl at 298 K is 0.0248 Scm-1. Calculate its molar conductivity.
- Q:-
What is the role of desorption in the process of catalysis?
- Q:-
Where does the water present in the egg go after boiling the egg?
- Q:-
[Fe(CN)6]4- and [Fe(H2O)6]2+ are of different colours in dilute solutions. Why?
- Q:-
Illustrate how copper metal can give different products on reaction with HNO3.
- Q:-
Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?
- Q:-
How are polymers classified on the basis of structure?
- Q:-
Which acid of each pair shown here would you expect to be stronger?
(i) CH3CO2H or CH2FCO2H
(ii)CH2FCO2H or CH2ClCO2H
(iii) CH2FCH2CH2CO2H or CH3CHFCH2CO2H
(iv)
- Q:-
Give structures of the products you would expect when each of the following alcohol reacts with (a) HCl-ZnCl2 (b) HBr and (c) SOCl2.
(i) Butan-1-ol
(ii) 2-Methylbutan-2-ol
- All Chapters Of Class 12 Chemistry
- All Subjects Of Class 12