calculate the no.of particles in 31g of P4 molecules. (atomic mass of P=31u)

No. of particles = Given mass / molarmass * Avogadro no.

                            = 31 / 4*31 * 6.022 * 10²³

                            = 6.022 * 10²³ / 4

                            1.5055 * 10²³ particles