Chapter 3 Key Terms Flashcards
The calculation of the quantities of material consumed and produced in chemical reactions
Chemical Stoichiometry
An instrument used to determine the relative masses of atoms by the deflection of their ions on a magnetic field
Mass spectrometer
Average mass of an element
Average atomic mass
Number equal to the number of carbon atoms in exactly 12 grams if pure 12C: Avogadro’s number. 6.022 • 10^23 units
Mole
The number of atoms in exactly 12 grams of pure 12C, equal to 6.022 • 10^23
Avogadro’s number
The mass in grams of one mole of molecules or formula units of a substance
Molar mass (molecular weight)
The percent by mass of a given element in a compound
Mass percent
The simplest whole number ratio of atoms in a compound
Empirical formula
Exact formula of a molecule, giving types of atoms and the number of each type
Molecular formula
Starting substance in a chemical reaction; on the left of a chemical equation
Reactants
A representation of a chemical reaction showing the relative numbers of reactant & product molecules
Chemical equation
Substance resulting from a chemical reaction; on the right of a chemical equation
Products
The ratio of moles of one substance to moles of another substance in a balanced chemical equation
Mole ratio
Making sure atoms are neither created nor destroyed and all atoms present in the reactants must be accounted for among the products
Balancing a chemical equation
Quantities of reactants mixed in exactly the correct amounts so that all are used up at the same time
Stoichiometric quantities
