Question

Trick to get valency of an element

Answer 1

by example I will get u the trick.
to know the valence of H(hydrogen)
*look at a famous/well known compound that includes hydrogen
*for e.g., H20
* in this valency of o is given to h and vice-versa
* so, frm this valency of h is 1.

another example,
to know the valency of Mg (magnesuim)
* look at compound MgO
*we already know valency of O is 2
*so, valency of Mg will be 2 as it cancel each other to form MgO.

hope it helps...