Answer:
you must know chemical formula of compound so you can determine the number of atoms and type of atoms in terms of which molecular formula is written. I choose Carbon dioxide so the formula of carbon dioxide is CO2. So it has two oxygen bind with one carbon atom.
find out the atomic number from periodic table, atomic number shows the number of protons in the nucleus of an atom of an element. and atomic number of Carbon is 6 and oxygen is 8 thus carbon has 6 protons while oxygen has 8 protons.
the number of protons and electrons are always equal in neutral atom thus carbon has 6 electrons and oxygen has 8 electrons.
find out the number of neutrons and you can find out it by subtracting atomic number from atomic mass. atomic mass of carbon is 12 and atomic number is 6 so number of neutrons= 12–6 = 6 neutrons in carbon while similarly oxygen has 8 neutrons.
since 2 oxygen atoms are there in CO2 now you should doubled number of protons, electrons and neutrons of oxygen that means 16p, 16n, and 16e. (p, n and e for protons, neutrons and electrons respectively)
Explanation:
