Question

The elements present in horizontal rows of a periodic table have same:

• A. atomic mass
• B. molecules
• C. valence shell
• D. valance electrons

Answer 1

The correct option is C valence shell

In a period, the valence shell of the elements remains the same as electrons are added to same outermost shell or else penultimate or anti penultimate shells. Thus correct answer is option $C$ valence shell.