Question

explain the term variable valency.why certain metals exhibits this phenomenon? give reason

pls ans this question
this is chemistry​

Answer 1

Answer:

some metals lose electrons from the shell next to the valence shell. In such a situation the element exhibits more than one electropositive valency. Such elements are said to have variable valency.

Some elements show variable valency because of the different electronic configurations. An atom of an element can sometimes lose more electrons than are present in its valence shell i.e. loss from the penultimate shell and hence exhibit more than 1 or variable valency.

Answer 2

The electrons which are present in an atom's outermost shell are called valence electrons. So one or more electrons from the core's outermost shell may also be lost after the removal of valence electrons. Such elements therefore indicate two or more different valencies i.e. they have variable valencies