OAT-Chemistry With Complete Solutions Latest Update
Accuracy - ANSWER a measurement giving the actual value for the sample with limited
deviation
Precision - ANSWER repeatability of a set of measurements on the same sample
Test tubes - ANSWER Good for small/large quantity of samples
Round bottom flask - ANSWER used for reaction, heating or vacuum
Retort - ANSWER round vacuum flask used for distillation
Buret - ANSWER Good for titrations, delivers liquid slowly
Volumetric pipet - ANSWER Delivers one premeasured volume of liquid with accuracy
and precision
Protons - ANSWER Equal to the atomic number (A) of an atom
Neutrons - ANSWER Equal number of to the number of protons
Electrons - ANSWER Equal to the atomic number, + charge indicates loss of electrons
and - charge indicates gaining of electrons
Mass number (A) - ANSWER Protons + neutrons
,Isotopes - ANSWER More than one atom that has the same number of protons and a
different number of neutrons (has different mass number)
Bohrs model of hydrogen - ANSWER E(energy value)=-Ry/n^2 (Ry=constant, n=quantum
number)
Anode - ANSWER Where oxidation occurs "An Ox"
Cathode - ANSWER Where reduction occurs "Red Cat"
Galvanic cells - ANSWER has a negative delta G and is a spontaneous reaction
Daniel Cell ANSWER Example of galvanic cell in which a zinc bar (anode) is placed in
aqueous ZnSO4 and a copper bar (cathode) is placed in aqueous CuSO4
Salt bridge ANSWER In a daniel cell, contains KCL or NH4NO3 whose ions will not react
directly with the electrodes or the ions in solution but permits the exchange on cations
and anions
Electrolytic cells - ANSWER have a positive delta G and is not spontaneous. Since it is
non spontaneous there is no salt bridge needed and everything can be placed in the
same container. Ex: battery
Anode of a galvanic cell - ANSWER is considered the negative electrode "The aNode of
a galvaNic cell is always Negative"
Faraday constant (F)- ANSWER one mole of electrons have the same charge as this. 1F=
96,487 Coulombs
Faraday equation- ANSWER This is used in calculating moles of electrons transferred by
an electrochemical cell _ X t= n X F i= current in amps, n= number of moles
, Reduction potential - ANSWER species in a redox reaction that will be oxidized or
reduced can be determined from this, defined as the tendency of a specie to acquire
electrons and be reduced
Standard reduction potential - ANSWER (E0) measured at standard conditions, higher E
means greater tendency for reduction to occur and lower E meaning greater tendency
for oxidation to occur
Standard electromotive force - ANSWER (EMF or E0 cell) is the difference in potential
between two half cells
Ecell= Ered + Eox
E cell is "+ in a galvanic cells and "-" in electrolytic cells
Gibbs Free Energy equation - ANSWER Delta G= -nFEcell
and
Delta G= -RT lnKeq
-When Keq>1 then the reaction goes forward
-When Keq<1 then the reaction goes in reverse
Nernst Equation - ANSWER Used when not at standard conditions.
Ecell= E0cell- (RT/nF)(lnQ)
rate determining step - ANSWER slowest step in a reaction because the over all reaction
cannot proceed faster than this step
reaction rate - ANSWER the change of concentration of reactant or finished product
with respect to time
Zero order reaction - ANSWER has a constant rate which is independent of the
reactants' concentration
Accuracy - ANSWER a measurement giving the actual value for the sample with limited
deviation
Precision - ANSWER repeatability of a set of measurements on the same sample
Test tubes - ANSWER Good for small/large quantity of samples
Round bottom flask - ANSWER used for reaction, heating or vacuum
Retort - ANSWER round vacuum flask used for distillation
Buret - ANSWER Good for titrations, delivers liquid slowly
Volumetric pipet - ANSWER Delivers one premeasured volume of liquid with accuracy
and precision
Protons - ANSWER Equal to the atomic number (A) of an atom
Neutrons - ANSWER Equal number of to the number of protons
Electrons - ANSWER Equal to the atomic number, + charge indicates loss of electrons
and - charge indicates gaining of electrons
Mass number (A) - ANSWER Protons + neutrons
,Isotopes - ANSWER More than one atom that has the same number of protons and a
different number of neutrons (has different mass number)
Bohrs model of hydrogen - ANSWER E(energy value)=-Ry/n^2 (Ry=constant, n=quantum
number)
Anode - ANSWER Where oxidation occurs "An Ox"
Cathode - ANSWER Where reduction occurs "Red Cat"
Galvanic cells - ANSWER has a negative delta G and is a spontaneous reaction
Daniel Cell ANSWER Example of galvanic cell in which a zinc bar (anode) is placed in
aqueous ZnSO4 and a copper bar (cathode) is placed in aqueous CuSO4
Salt bridge ANSWER In a daniel cell, contains KCL or NH4NO3 whose ions will not react
directly with the electrodes or the ions in solution but permits the exchange on cations
and anions
Electrolytic cells - ANSWER have a positive delta G and is not spontaneous. Since it is
non spontaneous there is no salt bridge needed and everything can be placed in the
same container. Ex: battery
Anode of a galvanic cell - ANSWER is considered the negative electrode "The aNode of
a galvaNic cell is always Negative"
Faraday constant (F)- ANSWER one mole of electrons have the same charge as this. 1F=
96,487 Coulombs
Faraday equation- ANSWER This is used in calculating moles of electrons transferred by
an electrochemical cell _ X t= n X F i= current in amps, n= number of moles
, Reduction potential - ANSWER species in a redox reaction that will be oxidized or
reduced can be determined from this, defined as the tendency of a specie to acquire
electrons and be reduced
Standard reduction potential - ANSWER (E0) measured at standard conditions, higher E
means greater tendency for reduction to occur and lower E meaning greater tendency
for oxidation to occur
Standard electromotive force - ANSWER (EMF or E0 cell) is the difference in potential
between two half cells
Ecell= Ered + Eox
E cell is "+ in a galvanic cells and "-" in electrolytic cells
Gibbs Free Energy equation - ANSWER Delta G= -nFEcell
and
Delta G= -RT lnKeq
-When Keq>1 then the reaction goes forward
-When Keq<1 then the reaction goes in reverse
Nernst Equation - ANSWER Used when not at standard conditions.
Ecell= E0cell- (RT/nF)(lnQ)
rate determining step - ANSWER slowest step in a reaction because the over all reaction
cannot proceed faster than this step
reaction rate - ANSWER the change of concentration of reactant or finished product
with respect to time
Zero order reaction - ANSWER has a constant rate which is independent of the
reactants' concentration