Question | Answer |
mass of an atom on the C-12 = 12.000000 u scale | (relative) atomic mass |
1/12th the mass of a C-12 isotope | atomic mass unit (amu, u, or 'dalton') |
modern 'standard' isotope for the relative atomic mass scale | carbon-12 (C-12) |
total mass of the atoms in the formula of any compound | formula mass |
total mass of the atoms in one molecule of a covalent compound | molecular mass |
mass in grams of an element equal to its atomic mass | gram-atomic mass (g.a.m.) |
mass in grams of a compound equal to its formula mass | gram-formula massn (g.f.m.) |
mass in grams of a covalent compound equal to its molecular mass | gram-molecular mass (g.m.m.) |
mass of a substance that contains one mole (6.02x10^23) particles | molar mass |
mole | amount of substance that contains Avogadro's # of representative particles |
mass relationships (Ex: % composition) derived from chemical formulas | formula stoichiometry |
% of the mass of a substance contributed by a particular element or part | percent (%) composition |
ionic compound with a set ratio of water molecules attached which stabilizes its structure | hydrate |
water molecules attached to the formula unit to stabilize the crystal structure of a hydrate | water of hydration |
meaning "without water", it describes the (powdery) form of a hydrate if the water of hydration is driven out | anhydrous |
name this compound: CuSO4•5H2O | copper (II) sulfate pentahydrate |
name this compound: CaCl2•2H2O | calcium chloride dihydrate |
write the formula for magnesium sulfate heptahydrate | MgSO4•7H2O |
simplest whole number ratio of atoms or ions forming a compound | empirical formula |
represents the # and kinds of atoms in one particle of a covalent compound, even if not the simplest ratio (Ex: butane = C4H10, not C2H5) | molecular formula |
volume of a gas that contains Avogradro's # (6.02 x 10^23) particles | molar volume |
molar volume of a gas under 'standard' conditions of temperature and pressure | 22.4 liters |
acronym for "standard temperature and pressure" | STP |
'standard' temperature on the celsius and kelvin (absolute) scales | 0 °C or 273 K |
'standard atmospheric (air) pressure" in atmospheres, torr (mm of Hg), and kilopascals | 1 atm or 760. torr (mm of Hg) or 101.3 kPa |
SI unit of pressure (equal to 1 N/m^2) | pascal |
1000 pascals or 1000 N/m^2 | kilopascal |
'honorary' name for 6.022 x 10^23 chemical units | Avogradro's number |
means "attached (or added) to" rather than "multiplied by" in chemistry | • |
molecular mass for water (H2O) | 18.0 grams |
representative particle for ionic (metal + nonmetal or polyatomic ion) compounds | formula unit |
representative particle for covalent (nonmetal + nonmetal) compounds | molecule |
representative particle for most elements | atom |
representative particle for diatomic elements | (diatomic) molecule |
diatomic elements mnemonic | BrINClHOF (or H + 7@#7) |
representative particle for NaCl | formula unit |
representative particle for H2O | molecule |
structured ('railroad tracks') system for performing chemical conversions (ex: grams <---> moles) | factor-label method |
factor-label method technique of checking and canceling units to make sure problem is set up correctly | dimensional analysis |
representative particle for Fe, Ne, Ca... | atom |
representative particle for H2, 02, Cl2... | molecule |