Mole Concept
Mole :
mole is defined as
It is chemical unit for Mass ,Number,and volume.
i.e mole is define as number, mass ,volume.
Now
we have arises question about what number ,how much mass and how many liter(volume) know as one mole.
☆Mole in term of number:~
Collection of 6.023×10^23 particale of any substance is equal to One Mole.
6.023×10^23 = NA(Avogadro number)
i.e in any substance of particales equal to avogadro number
Number of mole ={Total Given Number of particales÷NA}
Q1How many mole in 6.023×10^25 of oxygen(O2) molecule.
Solution
Given in term of number so we will Use formula of mole in term of number
No. Of mole ={given number÷NA}
{6.023×10^25÷6.023×10^23}
No of mole =100 of Oxygen molecules.
☆Mole in term of mass:~
Formula weight of substance in gram is equal to one mole
¤Number of mole ={Weight in gram ÷Formula wt.in Gram)
Note:
if weight no given in gram first we have to chage in gram then put in formula.
Formula wt:
¤O3(Ozone)~16×3=48gram.
¤H2O(Water)~ 1×2+16×1=18gram.
¤CaCO3(Calciumcarbonate)~ 40×1+12+16×3=100gm.
¤Mg(OH)2(Magnesiumhydrooxyed)~ 24×1+2×(16+1)=58 gm.
¤SO4^-2(Sulphate)~ 32×1+16×4=96gm.
¤C12H22O11(Sugar)~12×12+1×22+16×11=342gm.
Q2.How many mole in 64gm O2gas.
Solution:
Given in term of mass so use formula of mole in term of mass
No. of mole ={mass given in gram ÷Formula wt.}
=64÷(32)
=2mole
so Answer is 2Mole of O2.
¤ Mole in term of volume:: (only for gas and liqiued)
at standard temprature 25`c and 1ATM pressure .
22.4 liter of any substance(liq and gas) at standard temp &pressure is equal to one mole.
*Number of mole=(volume in liter÷22.4 liter)
Relations between in mole forms::
Mole also known as in different term for different substance given below
Substance Mole particles
1.Element - Gram- Atoms -Atom
eg:H(hydrogen)
,N(nitrogen),
O(Oxygen)
etc
2.Compound- Molar wt -Molecules
or gram-
molar
eg H20(water),
O2(molecular oxygen/atmospheric oxygen),
H2(molecular hydrogen/hydrogen)
etc.
3.Ion -Ionic weight(wt) - Ions
eg
Na^+ :Sodium ion
Mg^+2: Magnesium ion
So4^-2:sulphate ion etc.