a metal M forms an oxide having the formula M2O3. It belongs to III period of the Modern Periodic Table. Give atomic number and the valancy of the metal.
Here, M forms the formula M2O3 , it is clear that valency of M = +3 ( as valency of O =2)
Further, M is in third period so it must have the outer most 3rd shell with three valance electrons which gives it a configuration as:
(2,8,3)
So, the atomic no. of the M = 13 (its matching wth Aluminium metal)
Hence, the formula is Al2O3 .
Further, M is in third period so it must have the outer most 3rd shell with three valance electrons which gives it a configuration as:
(2,8,3)
So, the atomic no. of the M = 13 (its matching wth Aluminium metal)
Hence, the formula is Al2O3 .