Types of Chemical Reactions

Synthesis, DecompositionSingle & Double DisplacementComplete & Incomplete CombustionTypes of Reaction

element + element compoundelement + element compound

1. Synthesis (the hook-up)

1. Synthesis (the hook-up)

1. Synthesis (the hook-up)

Mg(s) + O2(g) MgO(s)Mg(s) + O2(g) MgO(s)

Metal + Nonmetal Ionic compound

Hydrogen + Nonmetal Simple acid

Nonmetal + Nonmetal Molecular compound

1. Synthesis (the hook-up)

1. Synthesis (the hook-up)

Example 1: Predict the products when calcium reacts with nitrogen gas

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

compound element + elementcompound element + element

2. Decomposition (the break-up)

2. Decomposition (the break-up)

2. Decomposition (the break-up)

Ionic compound Metal + Nonmetal

Molecular compound products may be unpredictable

2. Decomposition (the break-up)

2. Decomposition (the break-up)

Example 2: Predict the products when lithium chloride decomposes.

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

3. Single Displacement (cheater)

One element knocks out (“displaces”) another element in a compoundOne element knocks out (“displaces”) another element in a compound

Nonmetals swapped (females)

3. Single Displacement (cheater)

2CaO + I2 2CaI2 + O2

3. Single Displacement (cheater)

Metals swapped (males)

AB + Y YB + A

3. Single Displacement (cheater)

3. Single Displacement (cheater)

Mg(s) + 2HCl(aq) MgCl(s) + H2(g)Mg(s) + 2HCl(aq) MgCl(s) + H2(g)

Rule: only ions of the same type can switch

Metal replaces a metal, nonmetal replaces a nonmetal

3. Single Displacement (cheater)

3. Single Displacement (cheater)

Example 3: Predict the products when sodium nitrate reacts with aluminum

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

3. Single Displacement (cheater)

Example 4: Predict the products when beryllium fluoride reacts with sulfur gas

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

4. Double Displacement (the swap)

Two aqueous ionic compounds switch places with each otherTwo aqueous ionic compounds switch places with each other

AB + XY AY + XBAB + XY AY + XB

4. Double Displacement (the swap)

4. Double Displacement (the swap)

2KI+ Pb(NO3)2 → PbI2 + 2K(NO3)2KI+ Pb(NO3)2 → PbI2 + 2K(NO3)

4. Double Displacement (the swap)

Example 5: Predict the products when magnesium sulfate reacts with potassium iodide

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

4. Double Displacement (the swap)

Example 6: Predict the products when Lead (II) nitrate reacts with ammonium phosphate

Formula of reactants:Formula of products:Balanced chemical equation (add

states):

5. Combustion

Combustion reactions occur whenever oxygen is a reactant.

Energy is also released in the form of heat or light.

5. Combustion

Combustion reactions are further divided into these categories based on the substance being burned: Metal combustion Nonmetal combustion Hydrocarbon combustion

▪ Complete▪ Incomplete

5. Combustion

Combustion of Metals

Metal + oxygen gas metal oxide

2Mg + O2 2MgO

5. Combustion

Combustion of Nonmetals

Nonmetal + oxygen nonmetal oxide

C + O2 CO2

These are also classified as synthesis reactions.

5. Combustion

Combustion of Hydrocarbons

Hydrocarbon + oxygen gas ??

There 2 possible results depending on whether it is complete or incomplete

See next slides for more information

This occurs when all the carbons in the hydrocarbon is fully reacted with oxygen to form carbon dioxide.

Hydrocarbon + oxygen gas carbon dioxide + water

5a. Complete Combustion of Hydrocarbons

CxHy + O2 CO2 + H2OCxHy + O2 CO2 + H2O

5a. Complete Combustion of Hydrocarbons

CH4 + O2 CO2 + H2OCH4 + O2 CO2 + H2O

5a. Complete Combustion of Hydrocarbons

5b. Incomplete Combustion of Hydrocarbons

Occurs when not all of the carbons are fully reacted with oxygen

Results in carbon products that are connected to fewer than 2 oxygen atoms

Examples: Carbon with 1 oxygen = carbon

monoxide (clear colourless poisonous gas that kills by suffocation because your body thinks it is oxygen gas O2)

Carbon with no oxygen = carbon (e.g. coal or the black soot left in a fire pit and a BBQ)

5b. Incomplete Combustion of Hydrocarbons

• Hydrocarbon + oxygen gas water carbon dioxide + carbon monoxide + carbon

CxHy + O2 H2O + CO2 + CO + CCxHy + O2 H2O + CO2 + CO + C

5b. Incomplete Combustion of Hydrocarbons

Writing Chemical ReactionsGiven the reactants, predict the

products and classify the type of reaction

Write the chemical formulas for compounds in the reaction

Be aware of diatomic molecules, multivalents ions and polyatomics

Include the states of matterBalance the equation