Types of chemical reactions Synthesis Decomposition Single replacement Double replacement Combustion

Balancing an equation: since water has one oxygen and two hydrogen atoms, when water forms from the reaction of hydrogen gas and oxygen gas, the equation must show that twice as much hydrogen was used. 2H2 + O2 -----> 2H2O. Notice that the total number of atoms remains constant and that there is simply a rearrangement of the bonds

Synthesis: small units are combined to make larger units Synthesis: small units are combined to make larger units. Note the mistake in the animated movie below

Synthesis: zinc and sulfur combine explosively.

Synthesis: Sodium reacts with chlorine: each sodium releases an electron ; each chlorine picks up an electron.

More synthesis: phosphorus combines with chlorine

Ex: HgO ---> Hg + O2 (not balanced) Decomposition: smaller units are made by the breakdown of larger units. Ex: HgO ---> Hg + O2 (not balanced)

Double replacement: silver nitrate and sodium chloride trade places to form a precipitate of ?

Double replacement: the ions switch places. 07v06 Iron (III) chloride reacts with sodium hydroxide.

Single replacement: an ion takes the place of the element (or the element takes the place of the ion) Silver nitrate reacts with copper metal: Silver ions take the place of copper atoms 07v22

Combustion: reaction with oxygen; oxides are produced (this is a special type of combination reaction: oxygen combines with the elements which make up the substance). Propane is a common fuel.

Combustion: magnesium unites with oxygen to release light and heat energy. This can also be called a synthesis reaction. 03v06

Alcohol burns with a blue flame; if more oxygen is available, it will burn more vigorously

Optional: Polymerization Optional: Polymerization. Nylon results from two substances forming a chain of molecules called a polymer.