Chemical Reactions
Combination:
- A combination may be defined as a chemical reaction in which two or more substances combine to form a single substance under suitable conditions.
Decomposition:
Single Replacement:
Combustion:
Acid-Base:
- Combination reactions are also called synthesis reactions.
- A decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.
- Most decomposition reactions require an input of energy in the form of heat, light, or electricity.
- A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat.
- Combustion reactions must involve 02 as one reactant.
- The combustion of hydrogen gas produces water vapor.
- Acid-base reactions produces a salt and water
- When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt. The H(+) cation of the acid combines with the OH(-) anion of the base to form water.
Double Replacement:
- A single-replacement reaction is a reaction in which a more active metal displaces another less active metal in a compound
- Fe(s) + 2 HCl (aq) → FeCl2 (aq) + H2 (g)
- 2 Na(s) + 2 H2O (l) → 2 NaOH (aq) + H2 (g)
- In a double-replacement reaction, two ionic compounds in aqueous solution switch anions and produce an insoluble substance.
- either AD or CB is an insoluble compound, a precipitate will appear and there is a chemical reaction.
- BaCl2(aq) + K2CrO4(aq) → BaCrO4(s) + 2 KCl(aq)