Question

Give 3 significance of moles.

Answer 1

   Mole is an important concept in Atomic Chemistry and Atomic Physics. In stoichiometry mole concept is essential.  We have to calculations of quantities of reactants required to produce needed amounts of reactants.  Without mole concept it cannot be done.

      H2 SO4 + 2 Na OH ==> Na2 SO4 + 2 H2 O
           
          Here one mole of Sulfuric acid reacts with two moles of Sodium Hydroxide. It produces one mole each of Sodium Sulfate and two moles of water.


  Mole is a SI unit of measurement for amount of substance (matter) since 1971. One mole of atoms or a compound means Avogadro number of atoms or molecules respectively.  Avogadro number is N = 6.022 * 10²³.

  1 Mole of a substance means M grams of that substance, where M is the Molar mass.  For example: For H2 gas it is M = 2. For NaOH, M = 40.
  
  Mole concept allows us to treat atoms and molecules (compounds) in a similar fashion.  1 mole of any ideal gas occupies 22.418 Litres of volume at STP conditions.

  Ideal gas equations use the Mole Concept.  P V = n R T.  Here n is the number of moles.

  It is interesting to note that 23rd October is celebrated among Scientists as the Mole Day.

Answer 2

it is the fundamental quantity for amount of substance