Question

which of these elements is a metal?
a. hafnium (hf)
b. radon (rn)
c. silicon (si)
d. sulfur (s)
e. selenium (se)

Explanation:

Metals are typically found on the left and middle of the periodic table. Hafnium (Hf) is a transition metal in group 4, period 6. Radon (Rn) is a noble gas (nonmetal), silicon (Si) is a metalloid, sulfur (S) and selenium (Se) are nonmetals.

Answer:

A. hafnium (Hf)