exam 2 questions

Question 1

oxidation is the __ and reduction is the __

Answer 1

loss of electrons, gains of electrons

Question 2

of the species below, only is not a strong electrolyte

Answer 2

a. HCl
b. Rb2SO4
c. CH3OH
d. KOH
e. NaCl

answer: c

Question 3

aqueous potassium chloride will react with which one of the following in an aqueous solution to form a solid pressure

Answer 3

a. lead nitrate
b. calcium nitrate
c. sodium bromide
d. barium nitrate
e. sodium chloride

answer: a

Question 4

with which of the following will the sodium ion form an insoluble salt

Answer 4

a. chloride
b. sulfide
c. carbonate
d. nitrate
e. none of the above

answer: d

Question 5

which one of the following compounds is insoluble in water

Answer 5

a. Na2CO3
b. K2SO4
c. Fe(NO3)3
d. ZnS
e. AgNO3

answer: d

Question 6

which of the following is a weak acid?

Answer 6

a. HNO3
b. HCl
c. HCIO4
d. CH3COOH

answer: e

Question 7

the correct reaction between aqueous potassium hydroxide and aqueous hydrofluoric acid is

Answer 7

KOH(aq)+ HF(aq) -> H2O(l) + KF(aq)

Question 8

in which of the rxn is the element oxygen oxidized to a higher oxidation state

Answer 8

2H2O(l) -> 2H2(g) + O2(g)

Question 9

what are the ionic concentrations obtained by dissolving 0.850 mole of CaBr2 in water and diluting to 500 ml

Answer 9

1.7 M Ca^2+ and 3.4 M Br^-

Question 10

the net ionic equation for the dissolution of zinc metal in aqueous hydrochloric acid is

Answer 10

Zn(s) + 2H+ (aq) -> Zn^2+ (aq) + H2(g)

Question 11

which one of the following substances is produces during the reaction of an acid with a metal hydroxide

Answer 11

a. H2
b. H2O
c. CO2
d. NaOH
e. O2

answer: H2O

Question 12

which of the following is an oxidation-reduction reaction

Answer 12

Cu(s) + 2AgNo3 (aq) -> Zn^2+ (aq) + H2(g)

Question 13

mixing 1.00 mL of an aqueous solution with 9.00 mL of water represents a __

Answer 13

a. two-fold dilution
b. hundred fold dilution
c. titration
d. ten-fold dilution
e. nine-fold dilution

answer: d

Question 14

in which species does bromine have an oxidation number of zero

Answer 14

a. HBrO4
b. Br2
c. NaBrO3
d. Br-
e. HBr

answer: b

Question 15

which of the following conditions would always result in an increase in the internal energy of a system

Answer 15

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

Question 16

the reaction:
4Al(s) + 3O2(g) -> 2Al2O3 (s) △H rxn= -3351 kj/mol
is __ and therefore heat is __ by the reaction

Answer 16

a. endothermic, released
b. endothermic, absorbed
c. exothermic, released
d. exothermic, absorbed
e. thermoneutral, neither released nor absorbed

answer: c

Question 17

which one of the following is the correct rxn equation for the enthalpy of formation of the product species

Answer 17

N2(g) + 2O2 (g) -> N2O4 (g)

Question 18

what volume of 0.102M NaOH is required to neutralized 28.3 mL of 0.443M HCl

Answer 18

a. 123 mL
b. 0.123 mL
c. 0.160 mL
d. 0.0123 mL
e. 160 mL

answer: a

Question 19

the △E of a system that releases 12.4J of heat and does 4.2J of work on the surroundings is

Answer 19

a. -16.6J
b. -12.4 J
c. +8.2J
d. +16.6J
e. -8.2J

answer: a

Question 20

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

Answer 20

a. 2.9J
b. 0.13J
c. 5.8*10**-4 J
d. 0.13J
e. 29J

answer: e

Question 21

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

Answer 21

-967.2 kj/mol

Question 22

of the following, which is not a state function

Answer 22

a. enthalpy
b. energy
c. heat
d. temperature
e. pressure

answer: c

Question 23

which of the following is a statement of the first law of thermodynamics

Answer 23

energy lost by a system must be gained by the surrounding

Question 24

which of the following is an endothermic process

Answer 24

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

Question 25

which of the following is a statement of Hess’s law

Answer 25

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

Question 26

the wavelength of light has a frequency of 1.2010**13 s-1 is __ m

Answer 26

a. 25.0
b. 2.50*10**-5
c. 0.0400
d. 12.0
e. 2.5

answer: b

Question 27

the photoelectric effect is

Answer 27

the ejection of electrons by a metal when struck with photons of sufficient energy

Question 28

of the following transitions in the hydrogen atom, the __ transition results in the emission of the lowest energy photon

Answer 28

n=6 -> n=4

Question 29

__ orbitals are spherically symmetrical

Answer 29

a. 2p
b. 1s
c. 3d
d. 3s
e. both b and d

answer: e

Question 30

which of the following pairs of electron orbitals in the hydrogen atom have the same energy

Answer 30

a. 1s and 2s
b. 2s and 3p
c. 4s and 3f
d. 2p and 3p
e. 2s and 2p

answer: e

Question 31

which electron orbital for the hydrogen atom does not exist as a solution of Schrödingers equation

Answer 31

a. 2d
b. 2s
c. 2p
d. 1s
e. 3p