synthesis+reactions

A **synthesis reaction** involves two or more reactants combining in a chemical reaction to form one product.

It follows the general form **A + B --> AB**, where the ratios are not shown for simplicity's sake.

__Types of Synthesis Reactions:__

1. elemental combinations - formation of compounds from their respective elements.
 * example: hydrogen gas reacts with oxygen gas to form water: 2 H 2 (g) + O 2 (g) --> 2 H 2 O (g)
 * this reaction is used by the Space Shuttle orbiter's main propulsion rockets
 * fuel cells can use this reaction to produce electricity (see: Apollo spacecraft, hydrogen cars)

2. water combinations - addition of water to covalent compounds.
 * example: formation of carbonic acid from water and carbon dioxide: H 2 O (l) + CO 2 (g) --> H 2 CO 3 (aq)
 * natural acidification of rain water due to formation of carbonic acid
 * this reaction is a concern in the study of climate change due to the rising concentration of CO 2 in the atmosphere, causing ocean acidification
 * the existence of SO x in coal burning emissions creates acid rain (sulfurous and sulfuric acid)

3. metal oxides and water - formation of hydroxides.
 * example: magnesium oxide in water forms magnesium hydroxide: MgO (s) + H 2 O (l) --> Mg(OH) 2 (s)

Worksheets: and

Online practice

A demonstration showing the synthesis of zinc and sulfur.