I II III IV V

Chemical Reactions

Types of Chemical Reactions

A. Combination or Synthesis the combination of 2 or more

substances to form a compound

only one product

A + B AB

A. Synthesis

H2(g) + Cl2(g) 2 HCl(g)

Al(s)+ Cl2(g) AlCl3(s)2 3 2

A. Combination or Synthesis

Products: ionic - cancel charges covalent - hard to tell

B. Combustion

CH4(g) + 2O2(g) CO2(g) + 2H2O(g)

the burning of any substance in O2 to produce heat

A + O2 B

EX: Burning of natural gas, wood and gasoline

Na(s)+ O2(g)

C3H8(g)+ O2(g) 5 3 4

B. Combustion

Products: contain oxygen hydrocarbons form CO2 + H2O

CO2(g)+ H2O(g)

Na2O(s) 4 2

***Combustion reactions are a type of synthesis reaction

C. Decomposition

a compound breaks down into 2 or more simpler substances

only one reactant

AB A + B

C. Decomposition

2 H2O(l) 2 H2(g) + O2(g)

KBr(l) K(s) + Br2(l) 2 2

C. Decomposition

Products: binary - break into elements others - hard to tell

2NaHCO3(s) Na2CO3(aq) + CO2(g) + H2O(l)

D. Single Displacement or Replacement one element replaces another in a compound

metal replaces metal (+) nonmetal replaces nonmetal (-) Halogens are replaced by a more reactive

halogen

A + BC B + AC

D. Single Displacement or Replacement

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

Fe(s)+ CuSO4(aq) Cu(s)+ FeSO4(aq)

D. Single Displacement or Replacement

Products: metal metal (+) nonmetal nonmetal (-) free element must be more active (check activity series)

Br2(l)+ NaCl(aq) N.R.

Activity Series of the Metals

Lithium Potassium Calcium Sodium Magnesium Aluminum Zinc Chromium Iron Nickel Lead HydrogenHydrogen Bismuth Copper Mercury Silver Platinum Gold

Metals can replace other metalsprovided that they are above themetal that they are trying to replace.

Metals above hydrogen can replace hydrogen in acids.

Metals from sodium upward canreplace hydrogen in water

The Activity Series of the Halogens

Fluorine

Chlorine

Bromine Iodine

Halogens can replace other halogens in compounds, providedthat they are above the halogenthat they are trying to replace.

2NaCl(s) + F2(g) 2NaF(s) + Cl2(g)

MgCl2(s) + Br2(g) No Reaction

AB + CD AD + CB

E. Double Displacement or Replacement ions in two compounds “change partners” cation of one compound combines with

anion of the other

E. Double Displacement or Replacement

Pb(NO3)2(aq) + K2CrO4(aq) PbCrO4(s) + 2KNO3(aq)

Pb(NO3)2(aq)+ KI(aq) PbI2(s)+ KNO3(aq)

E. Double Displacement or Replacement Products:

switch negative ions one product must be insoluble (check

solubility table)

NaNO3(aq)+ KI(aq) N.R.

2 2