Question

can the valency of an element be variable ? if it can mention two such elements and show that how they form compounds.How are these compounds named

Answer 1

Yes! Valency of atom can be variable due to empty orbitals of the Valence shell. e.g,
if7 and Pcl5

Answer 2

Answer:

yes,the valency of an element can be variable. It can,for example, iron has a valency of 2 and 3. To distinguish between them ,