c1.1

Atomic Structure LITHIUM METAL - Atoms are in rows as it is a solid, they vibrate in their lattice structure. one of the atoms look like this (image on the right) : centre = nucleusred circles - protons (positive charge = +1)yellow circles - neutrons (no charge = 0)blue circles - electrons (negative charge = -1)shell / energy levelsNEON GAS - atoms are spreaded around and not touching as it is a gas. On the periodic table the numbers next to the symbols can represent different things. for example, on sodium (NA) the bottom number shows 11 is the proton number / atomic number. The top number shows 23 is the atomic mass / mass number. - This is worked out by adding the proton number and number of neutrons. A method to work out what the atom looks like is by using a P.E.N diagram: draw p.e.n and write if negative/positive/neutral fill in proton and electron ( stable atoms - no. of proton = no. of electrons) to work out neutrons take the mass number away from proton number draw the atom by: drawing the protons and neutrons in the nucleus put electrons on the shell ( remember the order of electrons on a shell is 2,8,8,18)