Tag: how

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

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Why does copper turns green on exposure to air ?

This happens because of corrosion of copper , as the copper is exposed to air it reacts slowly with water from the moisture present in air, carbondioxide and oxygen. And the product formed is a mixture of copper hydroxide and copper carbonate as shown below.

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.

Why ortho-nitrophenol is more acidic than ortho-methoxy phenol ?

To answer this we have to see the reactive nature of phenol and the substituents attached to it. Acidic behavior of phenol depends on the fact that how easily it can loose a proton and make phenoxide ion which is stabilized by resonance. The methoxy group being electron donating group increases the electron density of

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Why white phosphorus is more reactive than red phosphorus?

White phosphorus exists in p4 molecule. In the molecular strain is quite high and it tends to break it as early as possible. On the other hand red phosphorus exists as polymer like structure. In red phosphorus the molecules join to make long chains and that makes them chemically inert or less reactive. For study

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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

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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

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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

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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

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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

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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

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What are the methods of preparation of Aldehydes and Ketones ?

What are the chemical properties of Carboxylic Acids ?

How the eye accommodates  to light ?

#accomodation #of #light In our day to day life we face various exposure to light. The intensity of rays vary from source to source some are intense and some are very low. Here i am going to share about the working of Iris of eye. Iris is basically like the shutter of cameras, it adjusts

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Why owl can see in night ?

Interesting fact about Owl We all know that the owl is capable of night vision due its special eyes. But more than this I have noticed a unique feature in it. That is ,  it does not create or make any kind of noise while taking a flight. When the owl is going to fly

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