Final answer:
Elements in the same group on the periodic table typically have the same number of valence electrons, which are crucial for bonding and chemical reactions. Group 1 elements each have one valence electron, while Group 16 elements have six. The group number minus ten often gives the valence electrons for p block elements.
Step-by-step explanation:
Understanding the correlation between an element's group number and its number of valence electrons is fundamental in chemistry, particularly when analyzing the periodic trend of valence electrons. Most elements within the same group exhibit the same number of valence electrons, corresponding usually to the group number's first digit. Specifically, for elements in Groups 1 and 2, the group number indicates the number of valence electrons - for example, Group 1 elements have one valence electron, while Group 2 elements have two.
In the case of the p block elements, we determine the number of valence electrons by subtracting ten from the group number. Therefore, Group 13 elements have three valence electrons, Group 14 elements have four, and so on, culminating in Group 18, where elements possess eight valence electrons, corresponding to a complete outer shell, which grants noble gases their renowned stability.
This pattern holds with the exception of the transition metals (Groups 3-12), which have a more complex electronic structure that does not adhere to the simple counting rule. An element like hydrogen (Group 1) has one valence electron, whereas oxygen (Group 16) has six valence electrons.