exam 2 questions Flashcards
oxidation is the __ and reduction is the __
loss of electrons, gains of electrons
of the species below, only is not a strong electrolyte
a. HCl
b. Rb2SO4
c. CH3OH
d. KOH
e. NaCl
answer: c
aqueous potassium chloride will react with which one of the following in an aqueous solution to form a solid pressure
a. lead nitrate
b. calcium nitrate
c. sodium bromide
d. barium nitrate
e. sodium chloride
answer: a
with which of the following will the sodium ion form an insoluble salt
a. chloride
b. sulfide
c. carbonate
d. nitrate
e. none of the above
answer: d
which one of the following compounds is insoluble in water
a. Na2CO3
b. K2SO4
c. Fe(NO3)3
d. ZnS
e. AgNO3
answer: d
which of the following is a weak acid?
a. HNO3
b. HCl
c. HCIO4
d. CH3COOH
answer: e
the correct reaction between aqueous potassium hydroxide and aqueous hydrofluoric acid is
KOH(aq)+ HF(aq) -> H2O(l) + KF(aq)
in which of the rxn is the element oxygen oxidized to a higher oxidation state
2H2O(l) -> 2H2(g) + O2(g)
what are the ionic concentrations obtained by dissolving 0.850 mole of CaBr2 in water and diluting to 500 ml
1.7 M Ca^2+ and 3.4 M Br^-
the net ionic equation for the dissolution of zinc metal in aqueous hydrochloric acid is
Zn(s) + 2H+ (aq) -> Zn^2+ (aq) + H2(g)
which one of the following substances is produces during the reaction of an acid with a metal hydroxide
a. H2
b. H2O
c. CO2
d. NaOH
e. O2
answer: H2O
which of the following is an oxidation-reduction reaction
Cu(s) + 2AgNo3 (aq) -> Zn^2+ (aq) + H2(g)
mixing 1.00 mL of an aqueous solution with 9.00 mL of water represents a __
a. two-fold dilution
b. hundred fold dilution
c. titration
d. ten-fold dilution
e. nine-fold dilution
answer: d
in which species does bromine have an oxidation number of zero
a. HBrO4
b. Br2
c. NaBrO3
d. Br-
e. HBr
answer: b
which of the following conditions would always result in an increase in the internal energy of a system
a. the system loses heat and does work on the surroundings
b. the system gains heat and does work on the surroundings
c. the system loses heat and has work done on it by the surroundings
d. the system expands against a constant external pressure and loses heat
e. the system gains heat and has work done on it by the surroundings
answer: e
the reaction:
4Al(s) + 3O2(g) -> 2Al2O3 (s) △H rxn= -3351 kj/mol
is __ and therefore heat is __ by the reaction
a. endothermic, released
b. endothermic, absorbed
c. exothermic, released
d. exothermic, absorbed
e. thermoneutral, neither released nor absorbed
answer: c
which one of the following is the correct rxn equation for the enthalpy of formation of the product species
N2(g) + 2O2 (g) -> N2O4 (g)
what volume of 0.102M NaOH is required to neutralized 28.3 mL of 0.443M HCl
a. 123 mL
b. 0.123 mL
c. 0.160 mL
d. 0.0123 mL
e. 160 mL
answer: a
the △E of a system that releases 12.4J of heat and does 4.2J of work on the surroundings is
a. -16.6J
b. -12.4 J
c. +8.2J
d. +16.6J
e. -8.2J
answer: a
the specific heat capacity of lead is 0.13 J/g-K. how much heat in J is required to raise the temp of 15g of lead from 22C to 37C
a. 2.9J
b. 0.13J
c. 5.8*10**-4 J
d. 0.13J
e. 29J
answer: e
the enthalpy change for the reaction of 2H2(g)+ O2(g) -> 2H2O(g) is -483.6 kj/mol. therefore the enthalpy change for the reaction is 4H2(g) + 2O2(g) -> 4H2O(g) is
-967.2 kj/mol
of the following, which is not a state function
a. enthalpy
b. energy
c. heat
d. temperature
e. pressure
answer: c
which of the following is a statement of the first law of thermodynamics
energy lost by a system must be gained by the surrounding
which of the following is an endothermic process
a. combustion of methane
b. condensation of water vapor
c. liquid water freezing
d. evaporation of liquid water
e. dissolving NaOH(s) in water
answer: d
which of the following is a statement of Hess’s law
if a reaction is carried out in a series of steps, then △H for the reaction will the sum of the enthalpy changes for the individual steps
the wavelength of light has a frequency of 1.2010**13 s-1 is __ m
a. 25.0
b. 2.50*10**-5
c. 0.0400
d. 12.0
e. 2.5
answer: b
the photoelectric effect is
the ejection of electrons by a metal when struck with photons of sufficient energy
of the following transitions in the hydrogen atom, the __ transition results in the emission of the lowest energy photon
n=6 -> n=4
__ orbitals are spherically symmetrical
a. 2p
b. 1s
c. 3d
d. 3s
e. both b and d
answer: e
which of the following pairs of electron orbitals in the hydrogen atom have the same energy
a. 1s and 2s
b. 2s and 3p
c. 4s and 3f
d. 2p and 3p
e. 2s and 2p
answer: e
which electron orbital for the hydrogen atom does not exist as a solution of Schrödingers equation
a. 2d
b. 2s
c. 2p
d. 1s
e. 3p
