Topic 1 Stoicheometry Flashcards
(24 cards)
What is Absolute Zero in Kelvin?
0 K
On the Celsius scale, this is -273 °C
What is Avogadro’s constant?
6.022 x 10^23
This is the number of particles in 12g of 12C
Define atomic mass.
The mass of a single atom
What is a chemical reaction?
A reaction in which bonds in the reactants are broken and bonds in the products are formed, resulting in an energy change
What is a compound?
Two or more types of atoms chemically bonded together
Define concentration.
A measure of the amount of dissolved substance contained per unit of volume
What is an element?
An element contains atoms of only one type
What is the excess reactant?
The reactant which there is more of than needed to react with all of the limiting reagent
Define empirical formula.
The formula obtained by experiment, showing the simplest whole number ratio of atoms of each element in a particle of the substance
What is formula mass?
The mass of one formula unit of that substance
What does the structural formula show?
The arrangement of atoms and bonds within a molecule
Define heterogeneous mixtures.
Mixtures which have non-uniform compositions and hence their properties vary throughout the mixture
What are homogeneous mixtures?
Mixtures which have both uniform composition and uniform properties throughout the mixture
What is an ion?
An atom or molecule where the total number of protons is not equal to the total number of electrons
Define limiting reagent.
The reactant which will determine the theoretical maximum amount of product formed
What is molar mass?
The mass of a mole of a substance
Define mole.
The amount of substance that contains a number of specified species equal to Avogadro’s constant
What is molecular mass?
The mass of one molecule of that substance
Define mixture.
Physically combined pure substances
What is a pure substance?
A matter that has a constant composition
Define solute.
A substance that is dissolved into another (the solvent)
What is a solvent?
A substance that dissolves another (the solute)
What is percentage yield?
The experimental yield as a percentage of the maximum theoretical yield
Define yield.
The amount of product
