Question

Classify the following elements as metal, nonmetal, or metalloid: aluminum, fluorine, gallium, phosphorus, krypton, tellurium, thorium, barium and strontium.

Answer 1

Classification into metal, non-metal and metalloid is done as follows -

Metal - Aluminium, gallium, thorium, barium, strontium

Non-metal - Fluorine, phosphorous, Krypton

Metalloid - Tellurium

• Metals are the type of elements that show metallic properties, non-metal do not show metallic properties. Metalloids show less amount of metallic properties.
• Metals are found on the left side of the periodic table with few electrons in the outermost shell.
• Non-metals are found on the right side with an almost complete outermost shell.
• Metalloids have near to half of the electrons in the outermost shell.

Answer 2

• Metals are lustrous, opaque materials that efficiently carry heat and electricity.

• Nonmetals are materials that lack all of the characteristics of metals. They are excellent heat and electricity insulators.

• A metalloid is a chemical element that incorporates metals and nonmetals in its characteristics.

Therefore among Aluminum, Fluorine, Gallium, Phosphorus, Krypton, Tellurium, Thorium, Barium, and Strontium,

Metals will be : Aluminium, Thorium, Barium and Strontium.

Nonmetals will be : Fluorine, Phosphorus and Krypton.

Metalloids will be : Gallium and Tellurium.