Compounds are composed of more than one element. Their formulas
have more than one type of symbol showing the different elements
that compose that compound. Remember...
Slide 3
Constructed from the symbols of the elements composing the
substances. EXAMPLE: NaCl is made of sodium (symbol = Na) and
chlorine (symbol = Cl) Chemical Formulas Na Cl
Slide 4
A subscript is the little number that shows how many of each
kind of atom are in the compound They are written to the lower
right of the element symbol EXAMPLE: H 2 OHydrogen How many? Oxygen
How many? When no subscript is written, it is a 1 Subscripts 2 1 O
H H
Slide 5
The number that comes before the chemical formula and indicates
the number of molecules present. EXAMPLE: 6H 2 O6 tells you there
are six molecules of water Coefficients O H H O H H O H H O H H O H
H O H H
Slide 6
CompoundFormulaCommon Name Sodium ChlorideNaClTable salt
Dihydrogen MonoxideH2OH2OWater GlucoseC 6 H 12 O 6 Simple sugar
Oxygen gasO2O2 Carbon dioxideCO 2 Carbon dioxide Nitrogen gasN2N2
Chemical Formulas you must know: