stichiometry

[rohith14]

can you explain me about avagadro law.

[Russ]

Avogadro's Law?

Avogadro's number (6.02 * 10^23) is the amount of atoms in one mole of an element.

Consequently, if you have a given amount of something (in mole) you can calculate the amount of atoms.

[Sonic]

Avogadro's Law states that for an equal volume of gases at the same temperature and pressure there must be the same number of molecules.
It therefore follows that it is independent of the size of the molecules. Equal volumes of H2 and O2 at the same T and P will have the same number of molecules (and therefore moles)

Mathematically:

(p1*V1)/(T1*n1) = (p2*V2)/(T2*n2) = constant

the statement that one mole of gas at STP takes up 22.4dm^3 of space can be shown using this law