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stoichiometry defects in solid

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                                        Defects in solids Crystal defect - Any type of deviation or irregularities in ideal arrangement is called crystal defect These are of two types:- 1.point defect:-these are irregularities from ideal arrangement around a point in crystalline substance. 2.Line defect:-These are irregularities or deviation from ideal arrangement around entire row of lattice point in crystalline solid. Types of point defect:- 1. Stoichiometric defect:-These are point defect that do not disturb the stoichiometry of solid or formula of solid. these are also known as thermodynamic defect or intrinsic defect.                                topperslearn.blogspot.com Type of stoichimetric defects:- 1.vaccancy defects:-when some constituent particles are missing from crystalline solids known as vaccancy defects. 2.Interstitial defect:-in this defect some constituent particles are introduced in interstitial sites of crystalline solids is known as int

Crystal lattice and unit cell

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Crystal lattice :  A regular 3-dimensional arrangement of points in space is known as crystal lattice. There are only 14 possible crystal lattices. They are known as bravies lattice. he Seven Categories of Bravais Unit Cells Category Edge Lengths Internal Angles Cubic ( a  =  b  =  c ) ( a  =  �/i> = g = 90 o ) Tetragonal ( a  =  b     c ) ( a  =  �/i> = g = 90 o ) Monoclinic ( a     b     c ) ( a  =  �/i> = 90 o    g) Orthorhombic ( a     b     c ) ( a  =  �/i> = g = 90 o ) Rhombohedral ( a  =  b  =  c ) ( a  =  �/i> = g   90 o ) Hexagonal ( a  =  b     c ) ( a  =  �/i> = 90 o , g = 120 o ) Triclinic ( a     b     c ) ( a     �/i>   g   90 o ) Unit cell :  It is smallest portion of crystal lattice which whwn repeated again and again in all the direction is called unit cell. There are 6 parameters of unit cell: a,b,c - Edge length alpha, beta, gama : Bond angle There are two types of unit cell: 1.Primitive uit cell 2.Centered unit cell T

SOLID STATE

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The three states of matter : solid, liquid and gas are the result of molecular interaction. For any substance to be in a particular state of matter is a matter of strength of intermolecular forces which when strongest bring the molecules closest (as much as possible) and substance adopts definite volume and shape at room temperature. The same substance at three different temperatures (ii) Temperature above its m.p. but below b.p. Solids can be classified in two major categories on the basis of pattern of arrangement of constituent particles. (a) Crystalline Solid; (b) Amorphous Solid (a) Crystalline Solid: Solids in which constituent particles are arranged in long range ordered pattern. e.g. Salt, Diamond, Iodine (b) Amorphous Solid: Solids in which pattern is short range ordered or disordered. e.g. Plastic, Glass, Rubber. Amorphous solid are also known as super cooled liquid. Difference between Crystalline and Amorphous Solid Property Crystalline Solid     Amorphous S

ELECTROSTATIC

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FRACTIONAL (STATIC) ELECTRICITY Electricity produced when two bodies are rubbed with each other (due to transfer of electrons). BASIC PROPERTIES OF CHARGES like charges repels each other and unlike charges attracts each other. Conservation of charges-Total charge of an isolated system is always constant. It can be transferred from one body to another. Charges are additive in nature q 1 =5C , q 2  = -10C q = q 1  + q 2  = - 5C Quantization of charges-Charge on a body is integral multiple of electronic charge. [Electric charge-Fundamental particle of charge] Integral multiple means e, 2e, and 3e... Thus q= ±ne, where n=0,1,2,3... NOTE 1e = -1.6 ×10 -19 C 1proton= +1.6 ×10 -19 C 1 particle or He = +3.2 ×10 -19  C Quark's e/3, 2e/3 COULOMBS LAW: It states that force of attraction or repulsion between two charges is directly proportional to the product of magnitude of charges and inversely proportional to the square of distance between them. Combining t