A divalent metal oxide contains 60% of metal. What is atomic weight of metal?
wt of metal= 60 g
wt of oxygen= (100-60) g= 40 g
Eq. wt. of metal = wt. of metal/ wt of oxygen* 8
= 12
As metal is divalent, At. wt= Eq. wt* valency= 12*2 = 24
Define mole and explain its relation with mass, volume and number of particles.
One mole is the SI unit for the amount of substance or particles. The particles can be atoms, molecules or ions. Thus, it is the fixed collection of 6.023 x 1023 number of atoms, molecules, ions, electrons, protons, etc particles.
The fixed number 6.023 x 1023 is called the Avogadro's number.
Number of moles can be expressed in terms of mass, volume and number of particles as: