To determine the atomic number of the elements just above and below element X in the periodic table, we need to consider its position in the 4th period.
The periods in the periodic table represent the number of electron shells or energy levels an element's atoms have. Each period begins with the filling of a new electron shell. Since element X is in the 4th period, it means its atoms have electrons filling up to the fourth energy level.
Elements in the same period generally have similar properties, but their atomic numbers increase from left to right across the period. So to find the elements just above and below element X, we need to identify the elements in the same period whose atomic numbers are the closest, but smaller and larger than 108.
To do this, we can refer to the periodic table or use some knowledge of the elements. In this case, element X with atomic number 108 is Hassium (Hs), which is in the 4th period. The elements just above and below Hassium in the same period would be Seaborgium (Sg) with atomic number 106 and Bohrium (Bh) with atomic number 107.
Therefore, the atomic number of the element just above element X would be 106 (Seaborgium) and the atomic number of the element just below element X would be 107 (Bohrium).