Term | Definition |
isomers | compounds with the same molecular formula but different arrangements of the atoms in their molecules |
reactant | a substance consumed during a chemical reaction |
product | a substance formed during a chemical reaction |
combination reaction | reaction in which 2 (or more) substances combine to form one product |
mole (mol) | an amount of material (atoms, ions, or molecules) that contains Avogadro's number (NA = 6.022 X 10 ^23) of particles |
Avogadro's number (NA) | the number of carbon atoms in exactly 12 grams of the carbon-12 isotope; NA = 6.022 X 10 ^ 23. it is the number of particles in 1 mole |
Molar mass (M) | the mass of 1 mole o a substance. The molar mass of an element in grams per mole is numerically equal to that element's average atomic mass in atomic mass units |
molecular mass | the mass of one molecule of a molecular compound |
formula mass | the mass of one formula unit of an ionic compound |
stoichiometry | the quantitative relation between reactants and products in a chemical reaction |
law of conservation of mass | the principle that the sum of the mass of reactants in a chemical reaction is equal to the sum of masses of the products |
combustion reaction | a heat-producing reaction between oxygen and another element or compound |
percent composition | the composition of a compound expressed in terms of the percentage by mass of each element in the compound |
mass spectrometer | an instrument that separates and counts ions according to the mass-to-charge ratios |
molecule ion (M+) | the peak of highest mass in a mass spectrum; it has the same mass as the molecule from which it came |
mass spectrum | a graph of the data from a mass spectrometer, where m/z ratios of the deflected particles with a particular mass |
combustion analysis | a laboratory procedure for determining the composition of a substance by burning it completely in oxygen to produce known compounds whose masses are used to determine the composition of the original material |
limiting reactant | a reactant that is consumed completely in a chemical reaction. The amount of product formed depends on the amount of the limiting reactant available |
theoretical yield | the maximum amount of product possible in a chemical reaction for given quantities of reactant: also called stoichiometric yield |
actual yield | the amount of product obtained from a chemical reaction, which is often less than the theoretical yield |
percent yield | the ratio, expressed as a percentage, of the actual yield of a chemical reaction to the theoretical yield |