Neutralisation reaction

The reaction between an acid and base to give salt and water is called neutralisation reaction. here in the following reaction we can easily see how Hydrochloric acid is reacting with sodium chloride NaOH + HCl ———> NaCl + H2O the nature of salt formed is dependent on the type of acid or base , if

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Atomic models

Thomson’s model of an atom Thomson proposed the model of an atom to be similar to that of the Christmas pudding. Thomson proposed that An atom consists of a positively charged sphere and electrons are embedded into it. The negative and positive charges are equal in magnitude so the atom as a whole is electrically

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Atomic Structure

Dalton’s Atomic Theory In 1808 John Dalton published a new system of chemical philosophy in which he propose the following theory :- Matter consist of indivisible atoms. All the atoms of a given element have identical properties. Compounds are formed when atoms of different elements combined in a fixed ratio. Chemical reactions only involve the

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Distillation and fractional distillation.

Distillation is a type of separating process in which two miscible liquids are separated from each other by using their different boiling points. the one with lower boiling point , boils first and its vapours are passed through a condenser for cooling and droplets are received on the other side in a beaker. this process

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what is valency ? how to calculate it?

Valency :- “It is the combining capacity of an atom”. it also indicates the number of electrons that can be gained , lost or shared . It decides that how many bonds can be formed, it gives the idea of molecule formation and the type of bond formed. calculation of valency is a simple task

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Full explanation of mole concept.

The word mole means pile up . This concept originated from a simple problem that was faced by the scientists to calculate the reactions. they needed a concept that could relate number of molecules with the weight. A mole of a substance is equal to as many molecules of that substance as there are number

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A Short intro to acid, base and indicators.

Acid base and salts Acids:-  these are the substances that Are sour in taste. Turn blue litmus red. Give H+ ions. Can accept a pair of electrons. Base :- These are the substances that Are bitter in taste. Turn red litmus blue. Soapy in touch. Give OH– ions. How to recognise the acid and bases?

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Electricity

                              Introduction ELECTRICITY: This term came from the Greek word ELEKTRON which means Amber. So the story begins from  the year 600BC, Thales Of Miletus(a Greek philosopher) observed the attraction of amber towards fiber and other small particles when rubbed vigorously. Later around 1600 AD. William Gilbert also found that other substances besides amber ,

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Basics of chemical reactions and chemical equations.

Chemical Change The change which give rise to new substances with new properties that are totally different from the starting matter. 2H2 + O2     ———> 2H2O Chemical changes are normally accompanied by the following changes:- 1. change in state 2. Change in colour 3. Change in temprature 4. Evolution of gas Chemical reaction Representation

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How to balance the chemical equation?

The need of balancing the chemical equation. The law of conservation of mass , “ Mass can neither be created nor be destroyed during any chemical change”. So the number of atoms on both RHS and LHS must be equal in the chemical equation. We have to check the total number of atoms on RHS

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Why CH3 group is Ortho and para directing in? Toulene

IN CASE OF TOLUENE the methyl group attached to the ring, increases the electron density at ortho and para positions by resonance without changing anything at the meta position. Thus the attacking reagent directly attacks at the electron rich site , thus the methyl group is ortho directing. you can easily understand the movement of

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Why is water more acidic than alcohol?

THE ANSWER CAN BE UNDERSTOOD EASILY BY LOOKING AT THE FOLLOWING POINTS:- 1. In case of alcohol the Oxygen atom is joined to the alkyl group on one side and hydrogen atom on the other side, being electron releasing in nature the alkyl group increase the electron density on Oxygen atom , thus making it

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What causes Ionic bonds to form? Use NaCl (table salt) as an example to explain the formation of ionic bonds.

it is a very common question and common example too. i would love to answer. Most people say it is the bond formed due to the transfer of electrons, but this explanstion is not complete. Ionic bond is the bond formed due to strong electrostatic forces of attraction between two oppositely charged ions. here is

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Which is more acidic ortho methyl phenol or phenol?

the phenol is more acidic as compared to ortho methyl phenol because the methyl group is electron releasing group which will increase the electron density in the ring as well as on the carbon atom attached to -OH (hydroxyl group) thus -OH group will not release the H+ ion. but in case of phenol there

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How to revise Digestive system in an easy way?

Human digestive system includes two basic things Alimentary canal 2. Digestive glands 1 Alimentary canal : human alimentary canal is basically a pipe of varying diameter which is designed for the maximum absorption of food. human alimentary canal is complete that is it two different openings for the ingestion of food and excretion of waste

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The galvanised iron lost its zinc coating even after it doesn’t corrode. Why does this happen?

Lets look from a different angle corrosion is basically oxidation and in oxidation the electrons are lost. Here we have zinc coated on iron being more reactive the zinc will tend to loose the electrons even if the iron is exposed, even then being good conductor the electrons are given to the iron by the

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The second electron affinity of oxygen is positive, what does that mean?

Electron affinity is the amount of energy change during the addition of an electron to an isolated gaseous atom. It can be positive as well as negative. Negative electron affinity means that the energy is released during the addition of electron. Which is a favorable condition for gaining an electron. But positive value means that

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