Question

The electronic configuration of an element T is 2,8,8,1.
what is the group no. of T?
what is period no. of T?
how many valence electrons are there in an atom of T????
what is the valency of T?
is it a metal or non metal?

Answer 1

Group no. 1
Period no. 4
Valence electron. 1
Valency. 1
It is metal

Answer 2

Although we do not need to mention the actual name of the element unless mentioned but for your information it is Potassium ( chemical symbol K ).

( a ) Since, T has 1 electron in its outermost orbit it must belong to group IA ( modern notation group 1 )

( b ) We see that T has 4 shells, hence it must belong to period 4.

( c ) The valence electrons are the number of electrons in the outermost shell of an atom. Here the valence electron is 1 in number.

( d ) Since, T has 1 electron in its valence shell, it will donate one electron to form cation. Hence, it will have the valency 1 + .

( e ) Since, it is donating electrons to complete octet, it is a metal.