Tag: concept

How many atoms are there in 1 gram of carbon?

For  calculation of number of atoms we have to calculate the number of moles present in 1gram carbon. Multiply the number of moles with Avogadro number. Step I  Number of moles in 1 gram of carbon = given mass / molar mass Molar mass (molecular or atomic mass expressed in grams) = 12g So the

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How many oxygen atoms are there in 90g of H2O molecule?

1 molecule of H2O has 1 atom of oxygen. Firstly we will calculate the number of atoms in 90g of H2O. we will explain it in two steps:- Step I:- No.of moles of H2O = given mass / molar mass No. of moles = 90/18 = 5 moles No. Of molecules = No. of moles

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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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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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