If it’s acid + polyatomic ion (oxyacid) then change endings mass of one mole of a compound Molar mass – -ate→ -ic acid Molar mass is calculated by adding together the masses of all -ite→ -ous acid atoms in a compound EX. nitrous acid EX. Molar mass of H2O = mass O + mass H + mass nitric acid H -or- mass O + (2 mass H) 16.0g + 1.01g + 1.01g = 18.0 g/mole -OR- 16.0g + (2 1.01g) = 18.0 g/mole Ionic, polar, and nonpolar bonds Mole Conversions - it is possible to convert between moles, mass, volume (of gas), or representative particles using If 2.0 it’s ionic conversion factors and dimensional analysis to calculate If 2.0 it’s polar covalent number of moles and then convert to any other unit shown in If 0.4 it’s polar covalent the diagram below: If < 0.4 it’s nonpolar A polar molecule has a partial positive and partial negative Percent Composition, Empirical & Molecular Formulas side Polar covalent bonds form when not all atoms that share relative measure of the mass of each Percent composition - electrons attract them equally. different element present in a compound the simplest number ratio of atoms Empirical Formula - present in a compound Molecule Shape, Bond angles, and VSEPR Theory Calculate from the percent composition, using the following poem: VSEPR- Valence Shell Electron Pair Repulsion Model, an Percent to Mass* arrangement that minimizes the repulsion of shared and Mass to Mole unshared pairs of electrons around a central atom. Divide by Small Then Multiply Whole! ‘til Moles & Molar Conversions shows the number of each type of atom Molecular Formula - in a molecule. = 6.02 1023 particles Avogadro’s Number
If it’s acid + polyatomic ion (oxyacid) then change endings -ate→ -ic acid -ite→ -ous acid EX. nitrous acid nitric acid Ionic, polar, and nonpolar bonds If 2.0 it’s ionic If 2.0 it’s polar covalent If 0.4 it’s polar covalent If < 0.4 it’s nonpolar A polar molecule has a partial positive and partial negative side Polar covalent bonds form when not all atoms that share electrons attract them equally. Molecule Shape, Bond angles, and VSEPR Theory VSEPR- Valence Shell Electron Pair Repulsion Model, an arrangement that minimizes the repulsion of shared and unshared pairs of electrons around a central atom. Moles & Molar Conversions Avogadro’s Number = 6.02 1023 particles Molar mass – mass of one mole of a compound Molar mass is calculated by adding together the masses of all atoms in a compound EX. Molar mass of H2O = mass O + mass H + mass H -or- mass O + (2 mass H) 16.0g + 1.01g + 1.01g = 18.0 g/mole -OR- 16.0g + (2 1.01g) = 18.0 g/mole Mole Conversions - it is possible to convert between moles, mass, volume (of gas), or representative particles using conversion factors and dimensional analysis to calculate number of moles and then convert to any other unit shown in the diagram below: Percent Composition, Empirical & Molecular Formulas Percent composition - relative measure of the mass of each different element present in a compound Empirical Formula - the simplest number ratio of atoms present in a compound Calculate from the percent composition, using the following poem: Percent to Mass* Mass to Mole Divide by Small Then Multiply ‘til Whole! Molecular Formula - shows the number of each type of atom in a molecule.
chem_midterm_review_17-18.docx