Chemistry June Flashcards
Arrhenius acid/base
substance that produces hydrogen ions when dissolved in water vs produces hydroxide ions
Bronsted acid/base
Acid is a proton donor and a base is a proton acceptor
strong acid
ionises completely in water to form a high concentration of hydronium ions
strong base
dissociates completely in water to form a high concentration of hydroxide ions
concentrated acid
contains a large amount of acid in proportion to the volume of water
ampholyte
substance that can act as an acid or a base
hydrolysis
reaction of a salt with water
equivalence point
point at which the acid and base have completely reacted with each other
auto ionisation
reaction of water with itself to form hydronium and hydroxide ions
redox reaction
involves the electron transfer from one substance to another
heat of a reaction
energy absorbed or released in a chemical reaction
activation energy
minimum energy required for a reaction to take place
reaction rate
change in concentration of reactants or products per unit time
chemical equilibrium
a stage in a reversible chemical reaction when the rate of the forward reaction is equal to the rate of the reverse reaction
dynamic chemical equilibrium
a stage in a reversible chemical reaction when the rate of the forward reaction is equal to the rate of the reverse reaction and both the forward and reverse reactions are occurring continuously and simultaneously
what affects reaction rate
temperature, surface area, concentration, catalyst
what disturbs chemical equilibrium
concentration, temperature, pressure (increasing/decreasing volume)
le chateliers principle
when the equilibrium in a closed system is disturbed the system will reinstate a new equilibrium by favouring the reaction that will oppose the disturbance
what happens when pressure is increased (V is decreased)
the reaction that forms the least amount of gaseous moles of substance will be favoured
NB: when the pressure is increased, both the forward and reverse reaction rates increase because concentration of all reagents increases
If the no. of moles of gaseous reactants equals that of the products, no reaction will be favoured
what happens when you add a catalyst to a reaction in chem. E
Eq is not disturbed, forward and reverse reaction rates increase equally
What changes the Kc value
temperature only
what happens when you add a catalyst to a reaction in relation to a graph
forward and reverse reaction rates increase equally, gradient of all curves is steeper and equilibrium is reached sooner
galvanic cell
cell in which chemical energy is converted in to electrical energy
anode
the electrode where oxidation takes 1
cathode
electrode where reduction takes place
function of salt bridge
completes the circuit
maintains electrical neutrality
Functions of inert Pt electrode
conducts the electrons
provides a surface for the reaction to occur
hydrogen electrode conditions
electrolyte concentration of 1
Temperature of 25
Pressure of 1 atmosphere
cracking
chemical process where longer chain hydrocarbons are broken down into smaller more useful molecules
electrolyte
solution that conducts electricity through the movement of ions.
electrolytic cell
cell in which electrical energy is converted into chemical energy
electrolysis
process where electrical energy is used to produce a chemical change
combustion
reaction of a compound with oxygen
