Why Do Water Pipes Break In Winter!

Water is the most common liquid on earth which covers 71.4% of earth surface. It is the only chemical substance on earth that exists naturally in 3 states (solid, liquid and gas (vapors)). But there are some anomalies about water. Unlike most other liquids such as alcohol or oil, when water freezes, it expands by Read More

Characteristics of Chemical Reactions

A chemical reaction is a process in which new substances are formed with completely new properties. The substance which reacts in a chemical reaction are called reactant and the new substance produced as a result of chemical reaction are called products. But how can one identify or recognize that the reaction has been completed. So, Read More


Ozone is a rare formed oxygen. It has 3 oxygen atoms in it, arranged in a tiny triangle. The 3 atoms don’t get along well in this arrangement, so after some time ozone breaks up to release an atom. This atom can be quite dangerous, because it will react with almost anything. We all have Read More

Why Do Old Books Become Yellow with Time

We all have seen that old books become yellow and brittle with time. This is due to the presence of lignin. As we know paper is made from wood, wood in turn is made of carbohydrates like cellulose and lignin. Lignin is very complicated molecule that adds hardness to wood. More the lignin, harder is Read More

Variable Oxidation State Shown by Group 15 Element

Elements of group15 have 5 valence electrons in their valence shell. So they exhibit various oxidation state from – 3 to +5 as discussed below. Negative oxidation state:-  These elements has 5 electrons in the valence shells and require 3 more electrons to acquire nearest noble gas configuration but gain of 3 electrons is energetically Read More

General Properties of group–15 elements

Group 15 elements consists of following elements Element Symbol Atomic Number Configuration 1. Nitrogen N 7 [He]2s22p3 2. Phosphorous P 15 [Ne]3s23p3 3. Arsenic As 33 [Ar]3d104s24p3 4. Antimony Sb 51 [Kr]4d105s2sp3 5. Bismuth Bi 83 [Xe]4fs145d106s26p3 Electronic configuration: The atoms of group 15 have 5 valence electrons in the outermost shell 2 in s Read More

Distinction Between Primary, Secondary and Tertiary Alcohols

Primary Secondary and Tertiary alcohols can be distinguished by the following test/reactions. 1. Luca’s Test: In this test alcohols are treated with an equimolar mixture of concentrated HCl and anhydrous (called Lucas reagent) and the alcohols gets converted into alkyl halides. Since alkyl halides are insoluble in water, their formation is indicated by the appearance Read More


Finkelstein Reaction: When alkyl halide reacts with sodium iodide in the presence of Acetone. Alkyl iodide and Sodium halide is formed. For ex. Swarts Reaction: When alkyl Bromide or Chloride reacts with silver or mercurous fluoride , Fluoro halide are formed .for ex.   Hundsdiecker Reaction: Silver salts of carboxylic acids are decomposed by Bromine Read More


(1) Mass Percentage:         Mass % of component = (2) Volume Percentage:       Volume % of component = (3) Parts Per million:        (4) Molarity (M)                 If volume of solution is in ml then divide it by 1000 to change into liters Ex – (5) (6) (7) Number of gram equivalents = Equivalent Read More

Preparation of Phenols

Phenol is also called Carbolic acid. It was first isolated from coal Tar. But nowadays it can be manufactured synthetically (1) From Benzene Sulphonic Acid (2) From Diazonium Salts (3) From Grignard Reagent   (4) By decarboxylation of Sodium salt of Salicylic acid (5) From Cumene (6) From Benzene (Rachig’s Method) (7) From ChloroBenzene (Dow’s Read More