Final answer:
Potassium is a main-group metal, Iron is a transition metal, Neon is a nonmetal main-group element, and Uranium is an inner transition metal.
Step-by-step explanation:
The classification of elements as metals or nonmetals, and their further classification into main-group (representative) elements, transition metals, or inner transition metals can be answered based on their position in the periodic table:
- K (Potassium) - Metal, Main-group (representative) element
- Fe (Iron) - Metal, Transition metal
- Ne (Neon) - Nonmetal, Main-group (representative) element
- U (Uranium) - Metal, Inner transition metal
Potassium (K) is an alkali metal found in group 1 of the periodic table, which makes it a main-group element. Iron (Fe) is part of the group of transition metals, found in groups 3 through 12. Neon (Ne) is a noble gas and nonmetal, which is also a part of the main-group elements in group 18. Uranium (U) is classified as an inner transition metal, specifically an actinide.