Ionic Bonding   a sodium atom   a chlorine atom  In lesson 11 we
saw that when atoms either lose electrons or gain extra
electrons they are called ions. Atoms that lose an electron are
called cations ... and atoms that gain an electron are called
anions.  If you look at the diagrams of the sodium and chlorine
atoms you can see that sodium normally has eleven electrons in
shells around the nucleus. You can also see that chlorine has
seventeen electrons around its nucleus. Both of these atoms
would be happier if they had eight electrons in their outside
shells.  The easiest way for sodium to do this is for it to lose
an electron - and chlorine can do this by gaining an extra
electron.   Fill in these missing words ...  When atoms lose or
gain electrons they are called . If an atom gains an it is
called an anion. When an atom loses an electron it is called a .
A sodium atom has eleven and a atom has seventeen electrons.
You have had tries to get this right   The sodium atom and the
chlorine atom want to make t