Question

State the informations obtained from the formula of a compound.

Answer 1

• A compound is a pure substance in which two or more elements are combined chemically in a fixed ratio by mass.
• A compound is represented by a chemical formula.

The following information about a substance can be found in a formula:-
1. The elements that make up the compound. In${\mathrm{H}}_2\mathrm{O}$ , there are two elements i.e. hydrogen (H) and oxygen (O).
2. The number and type of atom in one molecule. In ${\mathrm{H}}_2\mathrm{O}$ there are two hydrogen atoms and one oxygen atom.
3. Mass of one molecule of the compound. The mass of one molecule of ${\mathrm{H}}_2\mathrm{O}$ is 18 g [(2 x 1)+16]