Question

Name a non-metal that has luster.

Answer 1

Hint Non-metals are those which are placed right side of the periodic table and luster means the compound has a shiny appearance. The non-metal that has luster is the allotropic form of the element having atomic number 6.

Complete answer:
Non-metals are those elements that are placed right side of the periodic table. Some of the properties of nonmetals are:
They are mostly gases, they do not generally conduct electricity and heat, they are not ductile and malleable, etc.
Luster means the substance has a shiny appearance and it can reflect the light but generally the non-metals do not have this property. Bur the allotropic forms of carbon like graphite and diamond have the property of luster.
Both graphite and diamond are very stable and can be found in nature. Graphite is the most stable and you must have seen it in the pencils. Graphite is also a good conductor of electricity and heat because in the structure of graphite there are hexagonal layers in which one electron remains free, and it can conduct electricity.
So, when the graphite is subjected to very high temperature and pressure the graphite will change into a diamond. Due to the property of luster, it is used in jewelry. But it cannot conduct electricity or heat because there is no free electron in its structure.

Note: Iodine is also a non-metal sometimes regarded as metalloid and has the property of luster. It belongs to group 17 of the p-block and its atomic number is 53. Because of the property of being luster, iodine is said to have the property of metals.