Answer;
The comparison that would be best is;
They are in the same group because they have similar chemical properties, but they are in different periods because they have very different atomic numbers.
Explanation;
- Beryllium (Be) is an element is the periodic table with an atomic number of 4, which means it has 4 protons in the nucleus and also 4 electrons in the energy levels, since the number of protons is equal to the number of electrons.
- Beryllium has an electron configuration of 2: 2, which means it has two valence electrons, and has two energy levels which means it occupies period two of the periodic table, and group two of the periodic table.
- Barium (Ba) on the other had, has an atomic number of 56, which means it has 56 protons and 56 electrons. Thus it has an electron configuration of; 2;8;18;18;8;2; this shows that it has 6 energy levels thus occupies period 6 and is in group two since it has two valence electrons.
