1.2 Amount of Substance Definitions Flashcards
(11 cards)
Define Atom economy (and equation)
The measure of the amount of starting material that end up as useful products.
Percentage atom economy = (Molecular mass of desired product/ sum of molecular masses of all reactants) x 100
Define Avogadro’s constant
The number of atoms, molecules or ions in one mole of a given substance
Define Concentration (and units)
The amount of substance per unit volume. Units given in g/dm^3 or mol/dm^3
Define Empirical formula
The smallest whole number ration of atoms of each element in a compound
Define Limiting reactant
The reactant that is completely used up since it limits the amount of products formed
Define Mole
The mass of a substance containing the same number of units as there are atoms in exactly 12g of carbon-12
Define Molecular formula
The actual ration of atoms of each element present in a compound
Define Percentage by mass (and equation)
A value representing the concentration of an element in a compound or a component in a mixture
Percentage by mass = (Mass of desired component/ Total mass of mixture) x 100
Define Percentage yield (and equation)
The percentage ratio of the actual yield of product from a reaction compared to the theoretical yield
Percentage yield = (Actual yield/Theoretical yield) x 100
Define Relative atomic mass
The average mass of an atom of an element compared to 1/12th the mass of an atom of carbon-12
Define Relative molecular mass
The average mass of one molecule of an element or compound compared to 1/12th the mass of an atom of carbon-12
