IB Chemistry HL 100113

Reactivity 2.1: How much? The amount of chemical change

#Reactivity 2.1.1

Chemical equations

Chemical equations show the ratio of reactants and products in a reaction.

Deduce chemical equations when reactants and products are specified.

Include the use of state symbols in chemical equations.

#Reactivity 2.1.2

Mole ratio of an equation

The mole ratio of an equation can be used to determine:

  • the masses and/or volumes of reactants and products
  • the concentrations of reactants and products for reactions occurring in solution.

Calculate reacting masses and/or volumes and concentrations of reactants and products.

Avogadro’s law and definitions of molar concentration are covered in Structure 1.4.

The values for Ar given in the data booklet to two decimal places should be used in calculations.

#Reactivity 2.1.3

Limiting reactants

The limiting reactant determines the theoretical yield.

Identify the limiting and excess reactants from given data.

Distinguish between the theoretical yield and the experimental yield.

#Reactivity 2.1.4

Percentage yield

The percentage yield is calculated from the ratio of experimental yield to theoretical yield.

Solve problems involving reacting quantities, limiting and excess reactants, theoretical, experimental and percentage yields.

#Reactivity 2.1.5

Atom economy

The atom economy is a measure of efficiency in green chemistry.

Calculate the atom economy from the stoichiometry of a reaction.

Include discussion of the inverse relationship between atom economy and wastage in industrial processes.

The equation for calculation of the atom economy is given in the data booklet.

Reactivity 1.4
Entropy and spontaneity (AHL)
Reactivity 2.2
How fast? The rate of chemical change