CHEM | LESSON 2 Flashcards
one or more reactants is converted to one or more products.
Chemical reaction
alters the physical state of a substance without changing its composition.
Physical change
a chemical reaction) converts one substance into another.
Chemical change
Chemical reactions involve:
Breaking bonds in the reactants (starting materials)
Forming new bonds in the products
Burning in air
Combustion
The loss of electrons.
Oxidation
The loss of electrons.
Reduction
Any reaction in which electrons are transferred from one species to another.
Oxidation-reduction redox reaction
The gain of oxygen and/or loss of hydrogen.
Oxidation
The gain of oxygen and/or loss of hydrogen.
Reduction
The process by which living organisms use O2 to oxidize carbon- containing compounds to produce CO2 and H2O. The importance of these reactions is not the CO2 produced, but the energy released.
Respiration
The oxidation of iron to a mixture of iron oxides
Rusting
The oxidation of colored compounds to products which are colorless.
Bleaching
In all cases, the reaction taking place in a battery is a redox reaction.
Batteries
The sum of the atomic weights in atomic
mass units (amu) of all atoms in a compound’s formula.
Formula weight
can be used for both ionic and molecular compounds; it tells nothing about whether a compound is ionic or molecular.
Formula weight
should be used only for molecular compounds.
Molecular weight
The amount of substance that contains as many atoms, molecules,
or ions as there are atoms in exactly 12 g of carbon-12.
Mole
The number of formula units in a mole is known as
Avogadro’s number
The number of formula units in a mole is known as
6.02214199 x 10^23
The formula weight of a substance expressed
in grams.
Molar mass
The study of mass relationships in chemical
reactions.
Stoichiometry
The reagent that is used up first in a
chemical reaction.
Limiting reagent
The mass of product formed in a chemical
reaction and recovered in the laboratory.
Actual yield
The mass of product that should form according to the stoichiometry of the balanced chemical equation.
Theoretical yield
Actual yield divided by theoretical yield times 100..
Percent yield
