In this article, we shall enumerate different schools of criminology and study pre-classical school or demonological school. Remaining schools of criminology will be discussed in subsequent articles. There are countless theories but they can be clearly classified into two groups: Scientific Theories which are considered “true” or “facts” because they have been found experimentally to […]
Science > Chemistry > Solid State > Magnetic Properties of Solids In this article, we shall study the magnetic properties of solids, classification of solids on the basis of their magnetic properties. Every substance has some magnetic properties associated with it. The origin of these properties lies in the magnetic moments associated with the electrons. […]
Science > Chemistry > Solid State > Defects in Crystal Structure In this article, we shall study defects in the crystal structure, sources of defects and their types. Source of Defects in Crystal Structure: At absolute zero, crystals tend to have a tendency to have a perfectly ordered arrangement. This arrangement at absolute zero represents the […]
Science > Chemistry > Solid State > Radius Ratio and its Significance The ratio of the radius of cations (r+) to the radius of the anion (r–) is known as the radius ratio of the ionic solid. The significance of radius ratio: It is useful in predicting the structure of ionic solids. The structure of […]
Science > Chemistry > Solid State > Tetrahedral Voids and Octahedral Voids In this article, we shall study two types of voids formed during hexagonal closed packing namely, a) Tetrahedral voids and b) octahedral voids. Let us consider a closed pack hexagonal packing in the first layer as shown. There are empty spaces between the […]
Science > Chemistry > Solid State > Packing in solids In this article, we shall study the different types of close packing of the constituent particles in solids. The Principle of Packing in Solids: In a crystal particle (atoms, molecules or ions) occupy the lattice points in the crystal lattice. These particles may be of […]
Science > Chemistry > Solid State > Numerical Problems on Type of Crystal Structure In this article, we shall study to solve problems to calculate the atomic radius, the distance between atoms in the unit cell and to decide the type of crystal structure. Example – 01: A naturally occurring gold crystallizes in face centred […]
Science > Chemistry > Solid State > Numerical Problems on Density of Solid In this article, we shall study to solve numerical problems to find the density of solid, edge length and volume of the unit cell. Example – 01: Silver crystallizes in face centred cubic structure. The edge length of a unit cell is […]
Science > Chemistry > Solutions and Their Colligative Properties > Osmosis and Osmotic Pressure In this article, we shall study the phenomenon of osmosis and osmotic pressure. Semipermeable Membrane: A semipermeable membrane is a membrane which allows the solvent molecules, but not the solute molecules through it. Examples: Cellulosde, cellulose nitrate, animal bladder. Osmosis: The spontaneous […]
Science > Chemistry > Solutions and Their Colligative Properties > Boiling Point Elevation and Freezing Point Depression In this article, we shall study two colligative properties of solutions, namely elevation of boiling point and depression in freezing point due to addition of solute. Elevation of Boiling Point: Boiling Point of a Liquid: Boiling point is […]