The question asks to identify which property is NOT typical of metals. We need to recall the general physical characteristics of metals and then compare them with the given options.
Correct Option: A) Brittleness is not considered a typical physical property of metals. Metals are generally malleable and ductile, meaning they can be deformed without breaking, unlike brittle materials.
The question asks for the specific term used to describe the shiny appearance of freshly cut metal surfaces. This is a fundamental property of metals and has a distinct scientific name.
A) Metallic lustre is the specific term used to describe the characteristic shiny appearance of metals. This shine is due to the presence of free electrons in metals that reflect light.
The question asks to identify a non-metal that exhibits metallic lustre in its solid form. This is a characteristic property of certain non-metals, which is an exception to the general rule that non-metals are dull.
B) Iodine — Iodine is a non-metal that exists as a dark-grey or purplish-black solid with a distinct metallic lustre. This property makes it an exception among non-metals, which are generally dull.
The question asks to identify a non-metal that conducts electricity, which is an exception to the general rule that non-metals are poor conductors. We need to recall the properties of common non-metals and their allotropes.
Correct Option: D) Graphite is an allotrope of carbon, a non-metal. Unlike most non-metals, graphite has a unique layered structure where each carbon atom is bonded to three other carbon atoms. The fourth valence electron of each carbon atom is delocalized and free to move throughout the layers, making graphite an excellent conductor of electricity.
The question asks to identify the most well-known characteristic of diamond, an allotrope of carbon. We need to evaluate each option based on the known properties of diamond.
Correct Option: A) The hardest known natural substance. Diamond's unique crystal structure with strong covalent bonds in a tetrahedral arrangement makes it exceptionally hard, making it the hardest known natural material.
The question asks about the general properties of solid non-metals. We need to recall the distinguishing physical properties of non-metals compared to metals to identify the correct characteristic.
Correct Option: C) Brittle and break easily when hammered