how are elements in one category the same or different from the elements in other categories
Elements within a category share similar characteristics or properties that set them apart from elements in other categories. These similarities can be based on various factors such as atomic structure, chemical properties, physical properties, and reactivity.
For example, elements in the same group on the periodic table share similar chemical properties due to having the same number of valence electrons. This is why elements in the halogen group, such as fluorine, chlorine, bromine, and iodine, all tend to exhibit similar behaviors in chemical reactions.
On the other hand, elements in different categories may have vastly different properties. For instance, metals tend to be shiny, malleable, and good conductors of electricity, while nonmetals are typically dull in appearance, brittle, and poor conductors. These differences stem from variations in atomic structure and bonding patterns.
Overall, the similarities and differences among elements within and between categories help organize the periodic table and provide insight into the behavior of elements in various chemical reactions and scenarios.