Question

Give two reasons to support your statement that carbon dioxide is a compound and not a mixture.

Answer 1

Here are key differences between compounds and mixtures that can help with identifying a substance either as a compound or a mixture:

1) In mixture the different substances are not chemically fused while in a compound the different elements making it are chemically fused.

2) Mixtures can be separated by simple mechanisms such as handpicking, heating and filtering while elements in compounds can be separated through chemical reactions.

3) Mixtures can varied in quantity of the constituting substances easily while in compounds you cannot vary the amount of the elements.

4) Substances making up a mixture maintain their individual chemical and physical properties while compounds have different chemical and physical properties from the elements that make them.

Examples of mixtures - air, beans and sand, salt water, flour and nail fillings.

Examples of compounds - Sodium chloride, carbon dioxide and water.

Carbon dioxide is a compound because:

i) It has different chemical and physical properties from the carbon and oxygen the makes it.

ii) You can only separate carbon from oxygen in carbon dioxide using a chemical reaction.

iii)You cannot vary the amount of carbon or oxygen in a carbon dioxide molecule

iv) Carbon and oxygen that make up the carbon dioxide are chemically bonded to form this compound.

Answer 2

Carbon dioxide (CO2) is a chemical compound.

A molecule of it is composed of a lone carbon atom and two oxygen atoms, each connected to the carbon atom by a covalent bond.

A compound is formed when 2 elements combine in a chemical reaction. The compound formed cannot be seperated into the constituent elements by any physical method, unlike mixtures. it doesn't show the properties of the elements combined in it (individual properties). hence as it shows all these characteristics, carbon dioxide is a compound.