2.3 Voc Flashcards
measured in GRAMS
Mass
measured in LITERS
Volume
standard temperature and pressure is 273.17 Kelvin (also known as 0 Celsius) and 1 atmospheric pressure. STP is needed to use molar volume.
STP
1 mole of any gas occupies 22.4 Liters at STP.
Molar volume
digits in a value that indicate the accuracy of an initial measurement, and express the confidence we have in that measurement
Sig figs
a convenient method of writing very large or very small numbers
Scientific notation
refers to the species present in a substance: usually atoms,
molecules (covalent compounds), or formula units (ionic compounds)
Representative Particles
(M) the mass of a molecule, expressed in atomic mass units.
Molecular mass
the SI unit of amount of substance.
Mole
the volume of 1 mole of a gas at STP (standard temperature & pressure)
Molar Volume
the mass of one mole of a substance.
Molar mass
is the smallest unit of a non-molecular substance, such as an ionic compound
Formula unit
the average mass of one formula unit, measure in atomic mass units
Formula mass
a technique that is used to change the units of a quantity without changing the quantity’s value.
Dimensional analysis
is the ratio of the mass of a substance to its volume
Density
a ratio or fraction that is numerically equal to one, which is used to multiply or divide a quantity when converting from one unit to another.
Conversion factor
states that any two samples of gas with an equal number of particles will have the same volume when they are held at the same pressure.
Avagrado hypothesis
the number of atoms or molecules in a mole of a substance
Avagrados constant
(amu) the SI unit of atomic and molecular mass.
Atomic mass unit
the mass of an atom, expressed in atomic mass units (amu) or sometimes (u). We will use “amu” in class
Atomic mass
a symbolic representation of an element or compound
Chemical Formula
the reactant in a chemical reaction that limits the amount of product that is able to form.
Limiting reactant
which states that atoms, and therefore mass, are neither created nor destroyed by chemical reactions.
Law of conservation of mass
a conversion factor derived from the coefficients of a balanced chemical equation interpreted in terms of moles
Mole ratio
the calculation of quantities in chemical reactions
Stoichiometry
