Final answer:
Oxygen is a nonmetal; Barium and Praseodymium are metals, with Barium being an alkaline earth metal and Praseodymium an inner transition metal; Iron is a transition metal; Neon is a nonmetal noble gas; and Germanium is a metalloid.
Step-by-step explanation:
To classify each of the listed elements as a metal, nonmetal, or metalloid, we will refer to the periodic table. The classification for each element is as follows:
Oxygen (O) is a nonmetal and more specifically, a chalcogen.
Barium (Ba) is a metal and falls under the category of alkaline earth metals which are main-group elements.
Germanium (Ge) is a metalloid, exhibiting properties intermediate between metals and nonmetals.
Iron (Fe) is a metal, and it is also classified as a transition metal.
Neon (Ne) is a nonmetal, belonging to the noble gases group.
Praseodymium (Pr) is a metal and an inner transition metal, part of the lanthanide series.