MOLE CONCEPT

       MOLE CONCEPT

                     Why mole concept? this is important to know as no fun would be there to learn without knowing the purpose of learning. ok..

                 you all know what a reaction is.. it is the change of reactants to products.For a reaction to be complete all the reactants that was taken should be converted to products. This literally means none of the reactants should remain after the reaction.This happens only if we take the reactant molecules in a definite ratio. eg 

      1.    H2 + Cl2      gives   2HCl

                                                   here if we take 1 molecule each of hydrogen and chlorine we will get the reaction complete..this is also possible if we take molecules in 1:1 ratio.
                          2.    N2 + 3H2      gives  2NH3
                                                    here if we take 1 molecule of nitrogen and 3 molecules of hydrogen we will get the raction complete..this is also possible if we take the molecules in the ratio 1:3
                                            In daily life we cannot count these molecules as they are extremely small..WHAT WE DO is find a relationship between the number of atoms and its mass.The concept used for this is known as mole concept../                                

                                                              The mole concept is an important topic in chemistry but not fully understood by most of the chemistry learner’s these days..  We can start the discussion of the term by quoting the law behind it which is Avagadro’s law.. The law states that every gas in same temperature,pressure and volume will contain equal numbr of particles.. By further investigation in the law it was proved that every element taken by weight equal to its gram molar mass will contain an amount of 6.022*10^23 number of atoms of the element.. There comes the use of the unit “mole” which refers to 6.022*10^23 number of particles..

                                        Now that we know how much a mole is lets see how we can use it on different quantity of substances.. By nw its normal tht  u should have asked urself that how can 1 gram of H2 and 12 gram of C12 have 1 mole even.. Now that is because by mentioning mole we are only talking about the number of particles of the substance(IT’S A NUMBER!!) . 
                                                             
                                                        Imagine you have 2 tennis balls each weighing 10g and 2 footballs each weighing 100g ( no kidding you have to imagine this in your mind. take a minute or two). So this means 2 tennis ball weights 20 grams in total and 2 footballs weights 200 grams in total.          
                                                          And now comes the fun part i am just going to reverse the sentence.So 20 grams of tennis balls and 200 grams of football will contain 2 of them respectively each(get it!!).. now same concept is applied to atoms.

                                       We can use the mole concept to find mass of an atom/molecule/compound from its molar mass.. For example; find the mass of a carbon atom: we know 12 gram of carbon contains 6.022*10^23  number of carbon atoms .. Therefore 1 atom will weight 12/6.022*10^23 ..

                                  We can also use the mole concept to determine the number of particles in a given sample.. It should also be said that at standard temperature and pressure (STP) 1 mole of every substance will have a volume of 22.4 L…..