Coefficient- In a chemical equation, the number written in front of a reactant or product; gives the smallest number of particles of the substance involved in the reaction.

Reactants- starting substances.

Products- substances formed during the reaction.

Synthesis Reactions- chemical reaction in which two or more substances react to produce a single product.

Combustion Reaction- oxygen combines with a substance and release energy in the form of heat and light.

Decomposition Reaction- a single compound breaks down into two or more elements or new compounds.

Single Replacement- A reaction in which the atoms of one element replace the atoms of another element in a compound.

Double Replacement- Involves an exchange of ions between two compounds.

When two elements react, the reaction is always a synthesis reaction.

Example:

2 Na (s) + Cl2 → 2 NaCl

Example:

C (s) + O2 → CO2

In a combustion a substance is always combined with a oxygen. Note: Oxygen is on the reactants side.

Example 2:

2 H2 (g) + O2 (g) → 2 H2O (l)

Single compound breaks down into two or more substances.

Example:

2NaN3(s) → 2 Na (s) + 3 N2

Atoms of one element replace the atoms of another element in a compound.

Example:

Cu (s) + 2 AgNO3 (aq) → 2 Ag (s) + Cu(NO3)2 (aq)

Exchange of ions between two compounds

Example:

KCN(aq) + HBr (aq) → KBr(aq) + HCN (g)

1.) Zn + Cu(NO3)2 → Cu + Zn(NO3)2 Double- Replacement Rxn

Answer: Single- Replacement Rxn

2.) Magnesium Chloride + Silver Nitrate → Combustion Rxn

Answer: Double Replacement Rxn: Magnesium Chloride + Silver Nitrate → Magnesium Nitrate + Silver Chloride

MgCl2 + AgNO3 → Mg(NO3)2 + AgCl

4.) 4 Fe (s) + 3 O2 (g) → 2 Fe2O3(s) Synthesis Rxn

Answer: Synthesis Rxn/Combustion Rxn – These are the only type of reactions that can go together.

5.) 2Al (s) + 3S (s) → Al2S3(s) Combustion Rxn

Answer: Synthesis Rxn

3.) NaClO3 → NaCl + O2 Synthesis Rxn

Answer: Decomposition Rxn