Chem Final Review

Homogenous

Composition is the same in proportion throughout (e.g., salt water)

Heterogenous

Composition is different in proportion throughout (e.g., stew)

Elemental

Only consisting of one element (e.g., O2, Ar)

Compound

Consisting of two or more elements

Molecules

Consisting of two or more atoms (e.g., O2, CH4)

Atoms

Consisting of one atom (e.g., Au)

Density

Mass divided by volume

Atomic number

Number of protons in an element

Electrons

Number of protons if not an ion, otherwise determined by the charge

Neutrons

Atomic mass minus protons

Atomic mass

Number on the top of the element or listed as in Titanium-47

Wavelength

Inversely related to frequency

Ground state

Closer to the nucleus

Excited state

Farther from the nucleus

Electron configurations

Arrangement of electrons in an atom

Ionic radius

Decreases across a period

Ionization energy

Energy required to remove an electron

Electronegativity

Ability to attract electrons

Metals

Malleable, low electronegativities, lose electrons

Non-metals

Non-malleable, higher electronegativities, gain electrons

Lewis Structures

Diagrams showing bonding pairs and lone pairs

Ionic Bonds

Transfer of electrons from metal to non-metal

Polar Covalent Bonds

Unequal sharing of electrons

Non-polar Covalent Bonds

Equal sharing of electrons

Metallic Bonds

Sea of electrons shared among metal atoms

Transition metal

Include charge in the name

Empirical Formulas

Simplest whole number ratio of atoms

Molecular Formulas

Actual number of atoms in a molecule

Combustion

Produces CO2 and H2O

Double Replacement Reactions

Form a precipitate

Stoichiometry

Calculations of reactants and products in chemical reactions

Gases

Governed by the ideal gas law PV=nRT

Molarity

Moles of solute per liter of solution

Acids

Source of H+ ions, pH under 7

Bases

Source of OH- ions, pH over 7

Bronsted-Lowry

Protons are transferred in reactions

2 electron domains, 2b 0nb

Linear

3 electron domains, 3b 0nb

Trigonal Planar

4 electron domains, 4b 0nb

Tetrahedral

4 electron domains, 3b 1nb

Pyramidal

3 electron domains, 2b 1nb

Bent

4 elevtron domains, 2b 2nb

Bent

Ionic

Soluble and Conductive

Polar Covalent

Soluble not conductive

Non-polar covalent

All no

Metallic

Conducts electricity in bulk phase and is malleable