What is a mole and why do you use it?

Answer 1

A mole is 6.022 x 1023 units of a substance, usually the number of molecules present. It is normalized to the mass of Carbon-12, which is 12 grams per mole. The mole is a convenient way to express how much of a substance is present, because you usually want to know how many atoms and molecules are present before and after a reaction, rather than just deal with grams and have to convert by molecular mass.

For eg:, A+water==== B, and if 8g of A is taken in an experiment, then how much grams of B can it yield is to be found out. Since the experimental quantities are in grams, you consider 1 mole as the mol.wt of that substance in grams.

So, if molwt of A is 26 and that of B is 20, the

1 mole of A= 1mole of B according to the above reaction.

Thus, 26g of A= 20g of B

so, 8g of A = x gram of B

hence, X= 8*20/26

Actually, practical yield is less than X due to experimental losses.

so percentage yield can be calculated by - Practical yield/ X *100.

Thus, the mole concept helps in arriving at these answers. If a molecule splits up in a reaction, even integral moles can be obtained i.e 1/2 mole or 3/4 mole.

Answer 2

Mole is a unit of concentration - an amount of substance containing a number of molecules or atoms equal to the number of atoms in 12 g of the isotope carbon-12. The symbol in SI is mol.

Answer 3

A mole is a unit of measurement in chemistry that represents the amount of substance. It is used to simplify calculations involving large numbers of atoms or molecules. It is based on the number of atoms in exactly 12 grams of carbon-12, which is approximately 6.022 x 10^23 particles, known as Avogadro's number.

Answer 4

They sleep.

Answer 5

nush