Question

magnesium, bromine, silicon, uranium, hydrogen, helium, boron, arsenic, platinum, iodine, carbon, antimony, polonium; categories: metal, nonmetal, metalloid

Explanation:

To solve this, we classify each element into Metal, Nonmetal, or Metalloid:

Step 1: Recall Element Categories

• Metals: Typically shiny, good conductors (e.g., Mg, U, Pt, Po).
• Nonmetals: Poor conductors, brittle (e.g., Br, H, He, I, C).
• Metalloids: Have properties of both (e.g., Si, B, As, Sb).

Step 2: Classify Each Element

Element	Category	Reason
Bromine	Nonmetal	Halogen, non-conductive
Silicon	Metalloid	Semiconductor, metalloid
Uranium	Metal	Actinide, metal
Hydrogen	Nonmetal	Gas, non-conductive
Helium	Nonmetal	Noble gas, non-conductive
Boron	Metalloid	Semiconductor, metalloid
Arsenic	Metalloid	Semiconductor, metalloid
Platinum	Metal	Transition metal, conductor
Iodine	Nonmetal	Halogen, non-conductive
Carbon	Nonmetal	Non-conductive (e.g., graphite is conductor but C is nonmetal)
Antimony	Metalloid	Semiconductor, metalloid
Polonium	Metal	Metallic properties, conductor

Final Classification

• Metal: Magnesium, Uranium, Platinum, Polonium
• Nonmetal: Bromine, Hydrogen, Helium, Iodine, Carbon
• Metalloid: Silicon, Boron, Arsenic, Antimony

(Connect each element to its category using the table above.)

Answer:

To solve this, we classify each element into Metal, Nonmetal, or Metalloid:

Step 1: Recall Element Categories

• Metals: Typically shiny, good conductors (e.g., Mg, U, Pt, Po).
• Nonmetals: Poor conductors, brittle (e.g., Br, H, He, I, C).
• Metalloids: Have properties of both (e.g., Si, B, As, Sb).

Step 2: Classify Each Element

Element	Category	Reason
Bromine	Nonmetal	Halogen, non-conductive
Silicon	Metalloid	Semiconductor, metalloid
Uranium	Metal	Actinide, metal
Hydrogen	Nonmetal	Gas, non-conductive
Helium	Nonmetal	Noble gas, non-conductive
Boron	Metalloid	Semiconductor, metalloid
Arsenic	Metalloid	Semiconductor, metalloid
Platinum	Metal	Transition metal, conductor
Iodine	Nonmetal	Halogen, non-conductive
Carbon	Nonmetal	Non-conductive (e.g., graphite is conductor but C is nonmetal)
Antimony	Metalloid	Semiconductor, metalloid
Polonium	Metal	Metallic properties, conductor

Final Classification

• Metal: Magnesium, Uranium, Platinum, Polonium
• Nonmetal: Bromine, Hydrogen, Helium, Iodine, Carbon
• Metalloid: Silicon, Boron, Arsenic, Antimony

(Connect each element to its category using the table above.)