Chapter 3 Student competencies

• Know how to write and to balance chemical equations.
• Write a balanced chemical equation for the combustion of a given hydrocarbon.
• Write a balanced chemical equation for the reaction of an alkali metal with water.
• Write a balanced chemical equation for a combination reaction.
• Write a balanced chemical equation for the thermal decomposition of metal carbonates.
• Know how to calculate the average atomic mass of an element.  Understand the origin of the atomic masses listed on the periodic table.
• Use the isotope masses and average atomic mass to calculate the fractional isotopic abundances.
• Know exactly how the amu unit is defined.
• Quickly and accurately calculate formula or molecular weights for a given substance.
• Calculate the percentage composition of a compound.
• Understand what a mole is; understand the basis for Avogadro's number.
• Calculate the molar mass of a given substance.
• Interconvert masses, moles, and number of atoms or molecules.
• Calculate empirical formulas from percent composition and from combustion analysis data.
• Understand and apply reaction stiochiometric principles to chemical reactions.
• Determine the theoretical yield for a reaction when given specific quantities of reactants.
• Identify limiting and excess reagents.
• Calculate the amount of remaining excess reagent.
• Use actual yield data to determine percent yields.