Atom
The smallest part of an element that can exist.
Compound
A substance made up of atoms of two or more elements, strongly joined together.
Molecule
A group of two ore more atoms, strongly joined together.
Clue: Atomic No. 1
Hydrogen
Clue: Atomic No. 4
Helium
Clue: Atomic No. 7
Lithium
Clue: Atomic No. 9
Beryllium
B
Boron
C
Carbon
N
Nitrogen
O
Oxygen
F
Fluorine
Ne
Neon
Na
Sodium
Mg
Magnesium
Al
Aluminium
S
Silicon
Phosphorus
P
Sulphur
S
Chlorine
Cl
Argon
Ar
Potassium
K
Ca
Cacium
Salt
NaCl
Sodium + Chlorine