Chemical Formulas are a type of shorthand for representing the elements in a compound. Element Symbols are included on the Periodic Table. Chemical symbols (Element symbols) from the periodic table are used for the individual elements e.g. H for hydrogen, C for carbon, O for oxygen, N for nitrogen, Ca for calcium and Na for Sodium. Substances that have two or more atoms bonded together, and therefore more than one element e.g. H2O are called compounds. See Examples of Compounds.
Chemical Formula and Equations - Subscripts
A chemical formula or equation shows the symbols of the elements in the compound and the ratio of the elements to one another. If a substance contains more than one atom of a particular element, this quantity is indicated in chemical formulas or equations using a subscript number after the element symbol. The subscript number refers only to the element it immediately follows. For example, the chemical formula for water is H2O which indicates that 2 atoms of Hydrogen combines with 1 atom of oxygen.
A chemical formula or equation shows the symbols of the elements in the compound and the ratio of the elements to one another. If a substance contains more than one atom of a particular element, this quantity is indicated in chemical formulas or equations using a subscript number after the element symbol. The subscript number refers only to the element it immediately follows. For example, the chemical formula for water is H2O which indicates that 2 atoms of Hydrogen combines with 1 atom of oxygen.
How to write a Chemical Formula or Equation using SubscriptsTo type or write a subscript for a chemical formula or equation just follow these simple instructions:
- Type in the formula or equation for example H2O
- Highlight the number
- Click Format
- Select Font... Decrease the font size of the number
- Under the heading Effects tick the Subscript Box
- The formula will now show the equation with the number in subscript - H2O
Chemical Formula and Equations
Chemical Formula and Equations - Examples and Meanings of SubscriptsFor example, the chemical formula for water is H2O which indicates that 2 atoms of Hydrogen combines with 1 atom of oxygen. The chemical formula for sodium chloride (Salt) is NaCl indicating that one atom of sodium combines with one atom of chlorine in a one-to-one ratio. Subscripts are added, following the element symbol, to indicate that the number of atoms of that element in the compound if it is greater than one. For example, the formula for magnesium bromide MgBr2 which indicates that one magnesium atom combines with two bromine atoms.
Meanings and Examples of Chemical Formula and EquationsThe following examples of Chemical Formula and Equations explain their meaning.
Example of Chemical Formula for Salt (Sodium Chloride) - NaCl
NaCl
Symbol Na indicates the element Sodium
Symbol Cl indicates the element Chlorine
No subscripts indicate only 1 atom for each element
Symbol Cl indicates the element Chlorine
No subscripts indicate only 1 atom for each element
Example of Chemical Formula for Water - H2O
H2O
Symbol H indicates the element Hydrogen
Symbol O indicates the element Oxygen
Subscript indicates 2 atoms of Hydrogen
Symbol O indicates the element Oxygen
Subscript indicates 2 atoms of Hydrogen
Chemical Formula and Equations - Common Chemical Formula List
The following list of Chemical Formula and Equations shows some of the most common chemical formulas.
The following list of Chemical Formula and Equations shows some of the most common chemical formulas.
Common Chemical Formula List
| |
Na
| Sodium |
H2O
| Water |
C6H12O6
| Glucose |
| C2H6O | Alcohol |
CaSO4
| Sulfate Group |
H2S
| Hydrogen Sulfide |
NaCl
| Salt |
O2
|
Oxygen
|
C2H6O
| Ethanol |
| C2H4O2 | Vinegar |
NH3
| Ammonia |
Mg
| Magnesium |
C2H4O2
| Acetic Acid |
C4H10
| Butane |
| NO3− | Nitrate |
Cu
| Copper |
N2
| Nitrogen |
CO2
|
Carbon Dioxide
|
H2SO4
|
Sulfuric Acid
|
CH4
|
Methane
|
C12H22O11
|
Sucrose
|
C3H8
|
Propane
|
NaHCO3
|
Baking Soda
|
F
|
Fluoride
|
F2
|
Fluoride
|
H2O2
|
Peroxide
|
C8H10N4O2
|
Caffeine
|
NaCl
|
Sodium Chloride
|
C9H8O4
|
Aspirin
|
HCl
|
Hydrochloric Acid
|
Zn(NO3)2
| Zinc |
CO
|
Carbon Monoxide
|
NaOH
|
Sodium Hydroxide
|
NaCN
|
Sodium Cyanide
|
Ca(CN)2
|
Calcium Cyanide
|
Au
| Gold |
I
|
Iodine
|
Sn
| Tin |
C6H6
|
Benzene
|
H2S
|
Hydrogen Sulfide
|
CH3COCH3
|
Acetone
|
H3PO4
|
Phosphoric Acid
|
C5H12
|
Pentane
|
CH3OH
|
Methanol
|
HBr
|
Hydrobromic Acid
|
H2CO3
|
Carbonic Acid
|
Ti
|
Titanium
|
NaClO
|
Sodium Hypochlorite
|
C2H6
|
Ethane
|
(NH4)2SO4
|
Ammonium Sulfate
|
C8H18
|
Octane
|
CuSO4
|
Copper Sulfate
|
C27H46O
|
Cholesterol
|
C7H6O2
|
Benzoic Acid
|
H2SO3
|
Sulfurous Acid
|
C6H12O6
|
Galactose
|
C6H8O6
|
Ascorbic Acid
|
CO2
|
Dry Ice
|
NaNO3
|
Sodium Nitrate
|
CaO
|
Calcium Oxide
|
HIO3
|
Iodic Acid
|
C3H6O3
|
Lactic Acid
|
MgBr2
|
Lactic Acid
|
H2O
|
Water Vapor
|
No Formula
| Oxide |
C
| Carbon |
H
| Hydrogen |
| CnH2nOn | Sugar |
O4S2-
| Sulfate |
N2O
| Nitrogen |
C6H8O7
| Citric Acid |
C8H18
| Octane |
C10H16O
|
Camphor
|
| AgI | Silver Oxide |
As4O3
|
Arsenic Trioxide
|
Au2O3
|
Gold Trioxide
|
Au2S
|
Gold Sulfide
|
| Br2 | Bromine |
Al2O3
|
Aluminium foil
|
Chemical Formula and Equations
The above list of Chemical Formula and Equations provides details of the common Chemical Formulas.
The above list of Chemical Formula and Equations provides details of the common Chemical Formulas.