Tag: the

Stobbe reaction and its Mechanism

It is a type of condensation reaction that involves the condensation of an aldehyde or ketone with succinic ester in the presence of sodium ethoxide or Potassium ethoxide to yield unsaturated ester acid . The complete reaction is as below. The mechanism involves 3 steps , and firstly the succinate is treated with base to

Continue reading

How the age of mummies , dead bodies and fossils is calculated?

The aging of different organisms is mainly calculated by the special technique called the Radiocarbon dating. In this technique the age of any specimen is calculated on the basis of the present amount of an isotope of a particular element. Isotopes are the atoms of an element that have same atomic number but different atomic

Continue reading

How many lone pairs of electrons are on the S atom in sulphur tetra floride (SF4) ?

In case of SF4 there are 6 electrons in the outermost shell of Sulphur, out of these 6 electrons, 4 are utilized in bonding with fluorine and thus two unshared electrons are there. Which leads to the lone pair as shown below. Contribute to make this site more informative.

What are Colligative properties ?

Actually the word co-ligative itself reveals that (“co” means each other and “ligative” means related) These are the properties which are related to each other. The colligative properties are those properties that depend on the number of solute particles in a solution or a mixture. “These properties don’t depend upon the nature of particles “.

Continue reading

Why is carbon important for forming complicated molecules? Or why carbon makes a large number of molecules ?

The answer to this question is very simple . There are two major reasons behind it. 1. Catenation :- It is the property by which the carbon can make long chains, branched chains and ring or cylic structural by joining with its own atoms. Due to this it can make a variety of molecules. 2.

Continue reading

Why H3PO3 is a diprotic acid? Give reason with structure .

Meaning of diprotic acid is that , it can loose two hydronium ions (H+) . For finding how many H+ ions it can give , we have to see its structure. Here it have only two hydroxyl groups that is -OH groups, and the hydrogen atoms joined to these only are ionisable. So only these

Continue reading

Preparation of chlorobenzene – Sandmeyer’s reaction

Chlorobenzene and bromobenzene can be prepared by treating bezenediazonium chloride with cuprous chloride or cuprous bromide. This reaction is also called Sandmeyer’s reaction.

Why sigma bond is stronger than pi bond?

Actually the sigma bond involves head to head overlapping of orbitals, due to which the overlapping takes place on a larger extent. That makes the bond more stronger as compared to pie bond. In pie bond there is a sidewise overlapping of orbitals which leads to lesser extent of overlapping and thus the bond formed

Continue reading

What are the factors that affect Vapour Pressure?

1.Temperature :- With increase in temperature the rate of vaporization also increase thus it creates more pressure. Moreover with increase in temperature the kinetic energy of the vapours also increase. 2. Nature of liquid:- The liquids with lower inter-particulate attractions have high vapour pressure as the formation of vapours is easy . Like acetone is

Continue reading

Semiconductor and its types.

The substances whose conductivity lies between 10-⁶ to 10⁴ ohm-¹ . The range lies between conductors and insulators. Types 1. n-type :- These type of semiconductors have excess electrons present in the lattice that are responsible for the conduction. These are formed when the group 14 elements like Silicon are doped with group 15 elements

Continue reading

Explanation of Paramagnetism, ferromagnetism, ferrimagnetism and antiferromagnetism .

1. Paramagnetism :- This is the phenomenon by which substances are weekly attracted by the magnetic field. It arises because the substances are magnetized in the same direction of the applied magnetic field. This property is shown by the atom, ions or the molecules that contain unpaired electrons. 2. Ferromagnetism:- This is the phenomenon by

Continue reading

Calculation of edge length and radius of atom.

Calculate the radius of copper atom if it crystallise in face centred cubic lattice and has a density of 8.93 g / cm cube. Solution Structure given = fcc For fcc , Z = 4 Density , d = 8.93 Molar mass , M = 63.55 Avogadro number = 6.2×10^23 Use the given formula In

Continue reading

Why we have to provide activation energy for completion of a reaction?

To understand this concept we must be aware of Threshold energy or activation energy. The threshold energy or the activation energy is the minimum amount of energy that is required for the conversion of reactants into the products . According to collision theory the reactant species collide with each other to make the product. But

Continue reading

What is the decreasing reactivity order of halogen hydracids (HCl, HI, HBr) for addition reaction of alkenes? Explain.

The decreasing order of reactivity will be as follows:- HI > HBr > HCl In case of reactivity the HI will be the most reactive and then HBr and least reactive will be the HCl. This is due to the fact that the reducing character of Iodine is highest and it can easily break the

Continue reading

What are the chemical properties of Haloalkanes and Haloarens ?

What are the methods of preparation of Haloalkanes and haloarenes ?