CHEMICAL REACTIONS

• Chemical reactions


  Processes in which a substance (or substances) is changed into one or more substances
• Reactants


  Everything written on the left side of the arrow in a chemical reaction
• Products


  Everything written on the right side of the arrow in a chemical reaction
• Chemical reactions obey the law of conservation of matter - matter can neither be created nor destroyed</b>
• Types of chemical reactions

  • Combination reaction
  • Decomposition reaction
  • Single displacement reaction
  • Double displacement reaction
  • Redox reaction
  • Combustion reaction
  • Precipitation reaction
  • Neutralization reaction
• Combination reaction


  A reaction where at least two elements or compounds combine to form a single product
• Decomposition reaction


  A reaction where a single compound breaks down to form at least two products
• Single displacement reaction


  A reaction where one element in a compound is substituted by another element
• Double displacement reaction


  A reaction where the two reactants exchange one atom
• Redox reaction


  A reaction that involves the transfer of electrons between two species
• Combustion reaction


  A reaction where flammable compounds react with oxygen
• Precipitation reaction


  A reaction where the mixing of two solutions results in the formation of a solid precipitate
• Neutralization reaction


  A reaction between an acid and a base, resulting in the formation of water and salt
• Balancing chemical reactions


  1. Count the total number of distinct atoms on the reactant and product sides

  2. Use fractions to balance atoms that are not equal

  3. Eliminate fractions by multiplying all coefficients by the least common multiple
• Balancing chemical reactions


  1. Multiply coefficients by 2

  2. 2[KClO3 → KCl + 3/2O2]

  3. 2KClO3 → 2KCl + 3O2
• We were able to balance the chemical reaction without actually going through the laborious process of trial and error
• Steps to balance the complete combustion of butane

  1. Balance C atoms

  2. Balance H atoms

  3. Balance O atoms
• The reaction is not balanced even without constructing the table
• Balance atoms that appear only once on the reactant and product side first
• Balanced reaction for complete combustion of butane

  C4H10 + 13/2O2(g) → 4CO2(g) + 5H2O(g) + heat
• If the coefficient is nowhere to be found in the choices, convert all coefficients to whole numbers by multiplying by 2
• Never waste time doing trial and error in balancing chemical reactions