1000?
1000000?
10000000000?
No it is 602200000000000000000000!!!
It is obvious that we cannot work with these large figures easily
That is why we have to use another unit to work out these calculations. Mole calculations are the solution to this.
There is this interesting relationship between the atomic mass of any element or the molecular mass of any compound. That is if the atomic mass of the element is taken in grams it contains
602200000000000000000000 of atoms= (6.022x1023)= This number is also called avagadro number= is considered as one mole
atomic mass of C is=12
so, if 12g of C is taken it contains avagadro number of C atoms and can also be referred as one mole of C atoms
Same rule applies for a molecule. We know we can calculate the molecular mass of any molecule by adding the atomic masses of each number of atoms in a molecular formula.
e.g CO2 molecular mass is (12+16*2)=44
So, if we take 44g of CO2 it contains avogadro number(6.022x1023) of CO2 molecules which also means 1 mole of CO2
Questions:
1. Calculate the number of moles in
i. 23g of Na
ii. 9g of H2O
2. Calculate the number of atoms in 39 g of K
Next about Relative Atomic mass
