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THE SOLID STATE

Solid State : The state of the substance in which it has definite volume and definite shape.
Crystalline Solids : The substances in which constituent particles have orderly arrangement.
Amorphous Solids : The substances in which constituent particles do not have orderly arrangement.
Space Lattice : A three dimensional orderly arrangement of identical points. This depicts the relative arrangement of constituent particles in the crystal.
There are five types of two dimensional lattices and 14 types of three dimensional lattices.
Unit Cell : A three dimensional group of lattice points that generates the whole lattice by translation or stacking.
Types of Cubic Unit Cells : Simple, Body-Centered (BCC) and face centered ( FCC ).
Face Diagonal = root(2) x Edge length (for cube)
Body Diagonal = root(3) x Edge length (for cube)
For FCC arrangement of atoms, radius of atom, r can be calculated by the formula,

r = (1/4) x Face Diagonal = (1/4) x root(2) x Edge length

For BCC arrangement of atoms, radius of atom, r can be calculated by the formula,

r = (1/4) x Body Diagonal = (1/4) x root(3) x Edge length

Packing fraction or atomic packing fraction is the percentage of the available space occupied by atoms in a packing. For CCP and HCP packing fraction is 74% while for BCC is 68%.
Density of a crystal is related to edge length and atomic mass (formula mass) by the formula :

d = (zM)/a³N_A

Point Defects : The defects caused by missing or misplaced atoms or ions in the crystals.
Schottky, Frenkel and Interstitial defects are stoichiometric defects.
Diamagnetic substances are weakly repelled by Magnetic field. They have all there electrons paired.
Paramagnetic substances are weakly attracted by Magnetic field. They have some electrons unpaired.
Ferromagnetic substances are strongly attracted by Magnetic field.
Transition Temperature : The temperature at which a substance starts behaving as a superconductor.

SOLUTIONS

Solution : A homogeneous mixture of two or more substances whose concentrations can be altered with in certain limits.
Saturated Solution : A solution which cannot be dissolve any more of the solute at a particular temperature.
Solubility : The amount of the solute present in 100g of the solvent in a saturated solution at a particular temperature.
Super Saturated Solution : A Solution in which the amount of solute present in 100g of the solvent at a particular temperature is more is more than its normal solubility at that temperature.
Mass Percent : Mass of Solute per 100 g of the solution.
Molarity : Number of Moles of solute per litre of the solution.(TEMPERATURE DEPENDENT)
Normality : Number of gram-equivalents of solute per litre of the solution.(TEMPERATURE DEPENDENT)
Molality : Number of moles of solute per kilogram of solvent.(TEMPERATURE INDEPENDENT)
Mole Fraction : Ratio of number of moles of a component to total number of moles.
Parts per Million : The Number of parts by mass of solute per million parts by mass of solution.
Vapour Pressure : The Pressure developed above the liquid at particular temperature at the equilibrium point.
Raoult's Law : The Vapour Pressure of a solution is equal to the product of mole fraction of the solvent and its vapour pressure in pure state.
Ideal Solution : The solution which obey Raoult's Law at all concentrations and also H_mix= 0 and V_mix=0.
Non-Ideal Solutions : The Solutions which show positive or negative deviations from Raoult's Law.
Azeotrope : The mixture of liquids whic boils at constant temperature like pure liquid and has same composition of component in liquid as well as vapour phase.
Colligative Properties : The properties of the solution which are independent of nature of solute but depend upon the concentration of the solute particles.
Molal Elevation Constant : The elevation in boiling point of the solution when its molality is unity. also called Ebullioscopic Constant.
Molal Depression Constant : The depression in freezing point of the solution when its molality is unity. also called Cryoscopic Constant.
Osmosis : The passage of solvent from pure solvent or solution of low concentration to solution of high concentration through semi-permeable membrane.
Osmotic Pressure : the excess Pressure that must be applied to the solution side to prevent the passage of solvent into it through SPM.
Isotonic Solutions : The solutions of same molar concentrations and same osmotic pressure at particular temperature.
Isopiestic Solutions : The solutions whose vapour pressure are equal at particular temperature.
Van't Hoff Factor : It is the ratio of normal molecular mass to observed molecular mass or the ratio of Observed Colligative property to Normal Colligative Property.

Some Formulae.....in pics.....

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