Question

Classify the following into element, compound and mixture:

soap

Answer 1

Soap can be classified as a mixture.

• This is because soap is a mixture of a number of fatty acids in which the number of Carbon $\left(\mathrm{C}\right)$ atoms in hydrocarbon chain varies (hydrocarbons in which the acidic Hydrogen $\left(\mathrm{H}\right)$ of $-\mathrm{COOH}$ group is replaced with Sodium $\left(\mathrm{Na}\right)$ or Potassium $\left(\mathrm{K}\right)$ cation).
• Soap does not have a fixed composition.

Element: An element is a pure substance that cannot be split into simpler substances.

• Example: Hydrogen $\left({\mathrm{H}}_2\right)$, Copper $\left(\mathrm{Cu}\right)$ etc.

Compound: A compound is a pure substance in which elements combine chemically in a fixed composition to give a compound.

• They can be broken down into elements that make up the compound by using chemical or electrochemical methods.
• The properties of the compound are entirely different from the elements from which it is formed.
• Example: Water $\left({\mathrm{H}}_2\mathrm{O}\right)$, Common salt i.e.; Sodium chloride $\left(\mathrm{NaCl}\right)$

Mixture: When two or more substances (elements or compounds or an element and compound) are mixed in any proportion.

• The components of a mixture can be separated by physical methods of separation.
• Example: A mixture of Sand and Iron $\left(\mathrm{Fe}\right)$ can be separated by the use of a magnet (physical process) where Iron gets attracted to the magnet leaving behind sand.