Final answer:
In the listed elements, Chromium (Cr) and Strontium (Sr) are classified as metals. The properties of metals typically include shininess and good conduction of heat and electricity. Krypton (Kr), Carbon (C), and Bromine (Br) are not metals.
Step-by-step explanation:
The elements you listed, specifically Chromium (Cr), Krypton (Kr), Carbon (C), Bromine (Br), and Strontium (Sr), are all present on the periodic table. Among them, only Chromium (Cr) and Strontium (Sr) are classified as metals. Chromium is a transition metal while Strontium is an alkaline earth metal. Both are known for their shininess and good conduction of heat and electricity.
Certain elements such as boron, silicon, germanium, arsenic, antimony, and tellurium lie on the metal-nonmetal dividing line of the periodic table, hence they are sometimes classified as metalloids or semimetals.
On the other hand, Krypton (Kr), Carbon (C), and Bromine (Br) are not metals. Krypton is a noble gas, Carbon is a nonmetal, and Bromine is a halogen.
Learn more about Metals and Nonmetals