Question

State the number of atoms present in each of the following chemical species.

${\mathrm{P}}_2{\mathrm{O}}_5$

Answer 1

Atom

An atom is the smallest unit of ordinary matter that forms a chemical element.

Atoms in ${\mathrm{P}}_2{\mathrm{O}}_5$

• ${\mathrm{P}}_2{\mathrm{O}}_5$ consists of phosphorus atoms and oxygen atoms.
• The number of atoms in ${\mathrm{P}}_2{\mathrm{O}}_5$is the sum of phosphorus atoms and oxygen atoms.

No. of phosphorus atoms = 2
No. of oxygen atoms = 5

Hence, the number of atoms in ${\mathrm{P}}_2{\mathrm{O}}_5$ is 7.