Question

What are three metalloids on the periodic table?

Answer 1

Metalloid comes under the category of elements which possess the basic properties that lie between the properties of metals and non-metals. There is no specific or standard definition to explain metalloids as well as there are no standard criteria to distinguish metalloids from metal and non-metals.

Complete answer:
Metalloids have properties in common with metal and non-metals but have some differences.

PROPERTY	METAL	NON-METAL	METALLOID
Physical state	Solid, liquid	Solid, liquid or gas	Brittle solids
Luster	Highly lustrous	Low	low
Conductivity	Good conductor	Poor conductor	Conductor only in certain conditions
Tensile strength	Highly tensile in nature	Low tensile	Low tensile
Sonority	sonorous	Non-sonorous	Non-sonorous
Corrosive property	Highly corrosive in nature	They have low corrosive tendency	They are used to protect corrosion of metal by applying them as an alloy.
Melting point	Sharp and high melting point	Low melting point	Melting point is in between metal and non-metal
Location on periodic table	$s,p,d,f$ blocks	In $s,p$ blocks	Located only in $p$ block
Thermal conductivity	high thermal conductivity	Low thermal conductivity	Thermal conductivity in between the metals and non-metals
Chemical properties	Highly reactive	Low reactivity	Low reactivity- chemical nature of metalloids is similar to non-metals.
Examples	Aluminium, gold, platinum, silver	Carbon, phosphorous, sulphur, nitrogen	Silicon, germanium, antimony

From the above table we can conclude that metalloids have in between properties of metal and non-metals. Metalloids exist are too brittle in nature and therefore they are not used in structural uses. Metalloids are located in $p$ orbital. When we move top to bottom metallic character increases therefore, metalloids are present in the middle of the periodic table.

Note:
Metalloids are capable of forming an alloy in a particular proportion like silicon-germanium. Metals are also known as semi-metals. They are represented as stair steps in the periodic table. Other metalloids are boron, arsenic, tellurium selenium etc.