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Flashcards in Mock Exam 2 Deck (17)
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1
Q

imagine a reaction in which compound A (which is a blue compound) react with compound B (which is a yellow compound) to give AB
A2 + B2 –> 2AB
What can you say about the color of compound AB?
a) it is blue
b) it is yellow
c) it is green
d) it is impossible to predict what the color of AB is from the information given

A

d) it is impossible to predict what the color of AB is from the information given

2
Q

which acid is the strongest

a) CH4
b) OH2
c) NH3
d) HF

A

d) HF

3
Q

when a bond forms between two atoms

a) energy is released to the surroundings
b) energy is absorbed for the surroundings
c) energy is neither created nor destroyed
d) the kinetic energy of the system falls

A

a) energy is released to the surroundings

4
Q

which is the strongest base?

a) -CH3
b) -OH
c) -NH2
d) F-

A

a) -CH3

5
Q

which is a stronger acid NH3 or H2O?

a) NH3, because N is more electronegative than O, and therefore is better able to stabilize the charge on the conjugate base
b) NH3, because N is less electronegative than O, and therefore is better able to stabilize the charge on the conjugate base
c) H2O, because O is more electronegative than N, and therefore is better able to stabilize the charge on the conjugate base
d) H2O, because O is less electronegative than N, and therefore is better able to stabilize the charge on the conjugate base

A

c) H2O, because O is more electronegative than N, and therefore is better able to stabilize the charge on the conjugate base

6
Q

When this reaction occurs
H2O + NH3 -OH + NH4_
do you think the final reaction mixture contains:
a) more reactants than products because H2O + NH3 are weaker acids and bases than -OH + NH4+
b) more reactants than products because H2O + NH3 are stronger acids and bases than -OH + NH4+
c) more products than reactants because H2O + NH3 are weaker acids and bases than -OH + NH4+
d) more products than reactants because H2O + NH3 are stronger acids and bases than -OH + NH4+

A

a) more reactants than products because H2O + NH3 are weaker acids and bases than -OH + NH4+

7
Q

what is the pH of a 0.10 M solution of HNO3?

a) 0.10
b) 13.0
c) 2.0
d) 1.0

A

d) 1.0

8
Q

what is the pH of a 0.10 M solution of KOH at 25 degrees C?

a) 0.10
b) 13.0
c) 2.0
d) 1.0

A

b) 13.0

9
Q

if the pH of a 0.020 M acid is 1.70 what does that tell you about the acid?

  1. the acid is completely ionized
  2. the acid is strong
  3. the acid is not completely ionized
  4. the acid is weak
    a) 1
    b) 3
    c) 1, 2
    d) 3, 4
A

c) 1, 2

10
Q

what is the percent ionization in a 0.10 M solution of an acid that has a pH of 3.75?

a) 1.78 x 10 ^-4 %
b) 17.8%
c) 0.178%
d) 1.78 x 10^-3 %
e) 1.78%

A

c) 0.178%

11
Q

what is the oxidation number of C in H2CO3?

a) +4
b) +2
c) -4
d) -3

A

a) +4

12
Q
in the reaction Zn + Cu2+ --> Cu + Zn2+
the zinc
a) is oxidized in the reaction
b) is reduced in the reaction
c) is metallized
d) is catalyst
A

a) is oxidized in the reaction

13
Q

which reaction is NOT a redox reaction

a) 2Na + 2H2O –> 2NaOH + H2
b) H2 + O2 –> H2O
c) H+ + H2O –> H3O+
d) 2Fe + 3S –> Fe2S3

A

c) H+ + H2O –> H3)+

14
Q

in nitric acid, HNO3, the formal charge and oxidation number on the N are

a) +1, +5
b) +1, -3
c) +1, +3
d) -1, +5

A

a) +1, +5

15
Q

if the bond dissociation energies of the products are less than the bond energies of the reactants what does this mean in terms of the energy change in the reaction?

a) the reaction is exothermic
b) the reaction is endothermic
c) there is no overall energy change because energy can neither be created nor destroyed
d) it depends on the temperature

A

b) the reaction is endothermic

16
Q

what is the enthalpy change for the reaction: CH4 + 2Br2 –> CH2Br2 + 2HBr

a) -184 kJ
b) + 184 kJ
c) - 76 kJ
d) + 76 kJ

A

c) -76 kJ

17
Q
what mass of sodium hydroxide would be required to react with 50 mL of 0.15 HCl?
NaOH(s) + HCl(aq) --> NaCl(aq) + H2O(l)
a) 7.5 x 10^-3 g
b) 7.5 g
c) 3.0 g
d) 0.30 g
A

d) 0.30 g