Question

Classify the following substance into elements, compounds and mixtures:

Glucose

Answer 1

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

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

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

Glucose $\left({\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\right)$ can be classified as a compound.

• This is because glucose is made up of three elements combined chemically i.e.; Carbon$\left(\mathrm{C}\right)$, Hydrogen $\left(\mathrm{H}\right)$ and Oxygen $\left(\mathrm{O}\right)$ having a fixed composition of 6:12:6 or 1:2:1.
• In the sense that glucose contains only one type of constituent particles which have identical chemical properties i.e.; $\left({\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\right)$ particles, it is a pure substance.
• The properties of the compound (glucose) are different from its elements (Carbon, Hydrogen and Oxygen).
• Glucose can not be broken down into its elements by physical processes. So a chemical process is required to break the bonds between the elements.