Tag: define

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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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

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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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What is aldol Condensation ?

Ald + ol Ald- Aldehyde ; ol – Alcohol. As the name suggests , this is a type of reaction which involve the formation of such a molecule which have “alcohol and aldehyde” functional groups.

Why the diastereomers of optically active compounds are optically inactive?

Firstly let us discuss what are optically active compounds? These are the compounds that rotate the plane of polarized light. Now Diastereomers are basically mirror images of two optically active compounds. They rotate the plane of polarized light, either to the left side or to the right. If they are present together, they cancel the

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What is the difference between molecular mass and formula mass?

In case of ionic compounds we have crystal lattice composed of ions. And there is a never ending pattern of ions and that made it difficult to calculate the molecular mass. Thus we used a simple method by taking the ratio of the ions and then adding their masses, like in case of NaCl ;

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What is the difference between stereoisomers, optical isomers and enantiomers?

Stereoisomers :- These are the compounds that have same molecular formula but different arrangement of atoms in the space. Optical isomers :- The compunds that have same molecular formula but they rotate the plane polarised light to the different side, right side-dextrorotatory and left levorotatory. Enantiomer :- These are the compounds that are mirror images

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What is a racemic mixture?

On the basis of Optical activity the compounds or isomers can be classified into two types:- Those rotate the plane polarised light towards right called the dextro rotatory compounds. Those rotate the plane polarised light towards left are called Laevo rotatory compounds. The equimolar composition of the above two isomers is called racemic mixture.

What will be the volume of water when it is heated from 0 degrees Celsius to 10 degrees Celsius?

According to CHARLES LAW “At constant pressure, The volume of a given mass of a gas increases or decreses by 1/273 of its volume at 0 ͦ  degree C for every one degree centigrade rise or fall in temperature”. Vol at 10 = vol at zero + 10 x vol at zero/273

How does the normality of a mixture equation change for different solutes?

Actually normality depends upon a simple formula that is :- Normality = Number of Gram equivalents / litre The term gram equivalents change as the valency of a substance changes . all the elements do not have same valence and hence it varies from element to element or molecule to molecule. And the term gram

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What is a chemical bond ?

Chemical bond may be defined as the force of attraction by which two atoms are held together. The chemical bonds lead to the formation of molecules and crystals. There are various kind of bonding that we see around us. Covalent bond A covalent bond is formed by mutual sharing of electrons between two atoms. For

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Terms related to mass

Atomic mass Atomic mass of an element is the relative mass as compared with an atom of carbon 12 and it is expressed in AMU. A.M.U. AMU is the Atomic mass unit and it is defined as the mass equal to 1 by 12th of the mass of carbon 12 isotope. 1 amu = 1.66056x

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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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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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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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