Magnetic Properties of Solids
Magnetic Properties of Solids : The magnetic properties of materials are due to magnetic moment associated with individual electron. Each electron in atom has magnetic moment which originates from two sources:
Read moreHere you can read articles related to class 12 chemistry chapter 1 solid state
Magnetic Properties of Solids : The magnetic properties of materials are due to magnetic moment associated with individual electron. Each electron in atom has magnetic moment which originates from two sources:
Read moreIntrinsic and Extrinsic Semi-conduction (n-type and p-type semi-conductance) : Silicon and Germanium are the most important commercial examples of semiconductors. The crystal structure of both silicon and germanium are similar to that of diamond.
Read moreValence Band Theory or Mechanism of Electrical Conductance : Lower energy band is filled with electrons called valence band while the empty higher energy band is called conduction band.
Read moreElectrical Properties of Solids : On the basis of electrical conductivity, solids can be classified into three types. (a) conductors (b) insulators and (c) semiconductors
Read moreImpurity Defect in Ionic Crystals : These defects in ionic crystals arise due to the presence of some impurity ions at the lattice sites or at the vacant interstitial sites.
Read moreFool’s Gold Defect : Because of the natural colour of iron pyrites and metallic lustre some samples of minerals shine like gold so have been nick-named as fool’s gold.
Read moreDefect in Non-Stoichiometric Crystals (Metal Excess Defect and Metal Deficient Defect) : Non-stoichiometric compounds are those in which the numbers of positive and negative ions are different in the ratios as indicated by their chemical formulae but crystal remains neutral.
Read moreDefects in Stoichiometric Crystals (Frenkel and Schottky defect) : Stoichiometric compounds are those in which the numbers of positive and negative ions are exactly in the ratios indicated by their chemical formulae.
Read moreElectronic and Atomic Imperfections or defects : Any deviation from perfectly ordered arrangement of constituent particles in crystal is called imperfection or defect.
Read moreCalculations Involving Density of Unit Cell : If we know the edge of a cubic crystal of an element or compound, we can easily calculate its density as described below:
Read moreRadius Ratio : In ionic solids, the ratio of radius of cation to radius of anion is called radius ratio.
Read moreFormula of compound and Number of voids filled : In ionic solids, the bigger ions (usually anions) form the close packed structure and the smaller ions (usually cation) occupy the voids (may be tetrahedral or octahedral).
Read moreLocation of Octahedral and Tetrahedral Voids in Unit Cell: In CCP arrangement one octahedral void is present at the body center of the cube and 12 octahedral….
Read moreSize of Octahedral void OR Relationship between radius of octahedral void (r) and radius of sphere (R)
Read moreSize of tetrahedral void OR Relationship between Radius of Tetrahedral Void (R) and Radius of Sphere (R) :: r = 0.225R
Read moreOctahedral Voids and Tetrahedral Voids : The octahedral void is formed at the center of six spheres. The tetrahedral void is formed at the center of four spheres.
Read moreHexagonal Close Packing in Three Dimensions: Let us mark the spheres in first layer as ‘A’. In the first layer there are some empty spaces called voids or holes.
Read moreStarting from the square close packed layer, the second layer and all further layers will be built up such that they are horizontally as well as vertically aligned with each other.
Read moreThe spheres in second row are exactly above those of the first row. The second row is exactly same as the first one. If we label the first row as ‘A’ type, the second row is also ‘A’ type.
Read moreCubic close packed structures help in understanding the packing of constituent particles in crystals. These spheres are packed in such a way that they occupy maximum free space and hence the crystal density is maximum.
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