Based on the information in the table, which two elements are most likely in the same group, and why? bismuth and thallium, because their atomic masses are very similar nitrogen and oxygen, because they were both first isolated in the same year sodium and thallium, because their names both end in the same suffix: -ium bismuth and nitrogen, because they have the same number of valence electrons

The answer would be Bismuth and Nitrogen because they have the same number of valence electrons.

Groups in the periodic table are arranged in columns. When it comes to neutral atoms, the number of valence electrons it has is equal to the main group of that element. For example, Bismuth is under group 5A of the periodic table. It has 5 valence electrons. If you look for Nitrogen in the periodic table, you will find it in Group 5A as well and this means that it also has 5 valence electrons. 

What are the choices?