AP Chemistry Outline
Chapter 3 – Calculations with Chemical Formulas and Equations
Antoine Lavoisier – He observed that the total mass of all substances present after a
chemical reactions is the same as the total mass before the reaction. This is known as the
law of conservation of mass.
With Lavoisier’s law, chemists may now make the inference that Atoms are neither
created nor destroyed during any chemical reaction.
Stoichiometry – The quantitative nature of chemical formulas and chemical reactions
All Alkali metals react with water to form their hydroxide compounds and hydrogen gas.
2K + 2H2O ? 2KOH + H2
2Na + 2H2O ? 2NaOH + H2
Combustion reactions are rapid reactions that produce a flame. Oxygen gas is a required
reactant in order for combustion to occur. When hydrocarbons react with oxygen gas,
they form CO2 and H2O. HOWEVER, when there is an insufficient quantity of O2,
carbon monoxide is formed. Even more severe restriction of O2 will cause the production
of fine particles called soot.
C3H8 + 5O2 ? 3CO2 + 4H2O
Combination reactions occur when two or more substances react to form one product.
Also known as synthesis. Magnesium burning with oxygen to from magnesium oxide is
2Mg + O2 ? 2MgO
When a combination reactions occurs between a metal and a nonmetal, the product is an
In a decomposition reaction, one substance undergoes a reaction to produce two or more
substances. Metal carbonates decompose to form metal oxides and carbon dioxide when
CaCO3 ? CaO + CO2