Question

In which group all the elements do not have
same number of valence electrons?​

Answer 1

Every element in a group have same number of valence electrons depending upon the group to which they belong...

Answer 2

Explanation:

modern periodic table is based on the atomic number of elements,what was the experiment which proved the significance of atomic number from the following

1)mullikan's oil drop experiment

• 2)moseley's work on x-ray spectra

3)Bragg's work on X-ray diffraction

4)discovery of x-rays by rongten