Question

10. The elements in the same period have :
(a) same number of electron shells
(c) different number of valence electrons
(b) different number of electron shells
(d) both (a) and (c)​

Answer 1

A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor.

Answer 2

Correct answer is Option (a) that is same number of shell

Periods are the horizontal row in the periodic table

Explanation :

Periods tell us the occupation of orbitals in the valence shell.

There are seven periods in the periodic table and these periodsbegin from extreme left.

Elements present in the horizontal row are Periods

Elements with the same number of electron shells are in the same period

So the correct option is Option (a) same number of electron shell.