Final answer:
Germanium (Ge) has physical and chemical properties most similar to Arsenic (As), as both are metalloids in Group 15 of the periodic table with similar bonding structures.
Step-by-step explanation:
The element with physical and chemical properties most similar to Arsenic (As) is Germanium (Ge). The properties of elements are influenced by their position in the periodic table, and elements that are in the same group tend to have similar properties. Arsenic and Germanium are both in Group 15, which is sometimes referred to as the pnictogens or the nitrogen group.
Both are metalloids with similar bonding structures; Arsenic has a layered structure with covalent bonds to three other atoms, while Germanium has a diamond-like structure with covalent bonds to four other atoms. But given the fact that both belong to Group 15, the chemical behaviors of Arsenic and Germanium are more alike than those of Silicon (Si), Phosphorus (P), or Lead (Pb).