Number of protons in one atom of P= Number of electrons in one atom of P=15
Number of neutrons in one atom of P=(A−Z)
=(30−15)=15
0.18 g 3015P=0.1830=0.006 mol
Number of atoms in 0.006 mol=0.006×6.02×1023
Number of protons in 0.006 mol 3015P=15×0.006×6.02×1023=5.418×1022
So, Number of electrons =5.418×1022
and Number of neutrons =5.418×1022.