Question

Pick out which among the following are not compounds?
Chlorine gas, Diamond, Iron powder, Aluminium foil, Iodine vapour, Graphite, Carbon monoxide, Sulphur powder, Iron Sulphide , Potassium chloride.

Answer 1

Hint :We must remember that a compound is when multiple elements combine together to form an end product. Some elements cannot exist in its natural state, hence in order to maintain a balance, combine with two or more different atoms and as a result form a compound. Also remember that a single element may have multiple ways of existing on its own, it may be as a solid, liquid or gas.

Complete Step By Step Answer:
An element is one that is pure, and that exists with only a single kind of atom. They cannot be further divided into any constituent elements. A compound on the other hand is a combination of multiple elements together. A compound is something that can be very well separated into its constituent or individual elements.
Let us take a look at the given components;
Chlorine gas – it is chlorine alone in its gaseous state, hence it cannot be a compound.
Potassium chloride – it is made up of potassium and chlorine, they are two different elements so it is a compound.
Iron powder – is iron in its powdered form, it is also not a compound.
Iron Sulphide – it is made up of iron and sulphur, which are different elements, so it is a compound.
Aluminium foil – it is aluminum on its own so it is not a compound.
Iodine vapour – it is iodine in its vapour state, so it is not a compound.
Graphite – it is a carbon in its crystalline form so it is not a compound.
Carbon monoxide – it is a combination of carbon and oxygen, so it is a compound.
Sulphur powder – it is made up of sulphur only, so it is not a compound.
Diamond – is made up of only carbon atoms, so it is not a compound.
So all together we can say from the given list, that the following elements are not compounds; chlorine gas, iodine vapour , diamond ,iron powder, aluminium foil, , graphite, sulphur powder.

Note :
We know that diamond is not a compound, because it is made up of only carbon atoms. But if diamond is an element, it is still not present on the periodic table. This is because diamond is an allotrope of carbon, which means that it is formed by carbon itself but due to changes like pressure, temperature or even light, carbon can exist in other forms.