CHAPTER 14 Flashcards
The general chemical equation for the dissolution of an acid in water is:
HA + H2O ↔ H3O+ + A-
Which statement about the acid equilibrium constant for this equation is true?
The denominator is [HA].
The numerator is [HA].
The numerator is [HA] [H2O].
The denominator is [HA] [H2O].
The denominator is [HA].
A base is added to water and the conductivity of the solution is high. From this observation, we conclude that the the base is:
strong, and does NOT ionize significantly.
strong and ionizes significantly.
weak, and does NOT ionize significantly.
weak and ionizes significantly.
strong and ionizes significantly.
Which statement about Bronsted-Lowry definition of acids and bases is true.
none of these
Acetic acid is always an acid because the word “acid” is in its name.
Any one substance can only ever be an acid, or it can be a base. Acids donate protons, bases accept protons.
The definition of an acid and a base is based on what the substance does in a particular context. This means that a particular substance can be an acid in one context and a base in another context.
The definition of an acid and a base is based on what the substance does in a particular context. This means that a particular substance can be an acid in one context and a base in another context.
Which statement about BrØnsted-Lowry acids and bases is true?
An acid accepts a proton and a base donates a proton.
An acid will always have the word “acid” in it. A base always contains hydroxide ion.
An acid donates a proton and a base accepts a proton.
none of these
An acid donates a proton and a base accepts a proton.
Acetic acid (CH3COOH) is a weak acid. You would therefore expect that a solution of acetic acid would contain:
a large number of acetic acid molecules and many ions.
a small number of acetic acid molecules and few ions.
a small number of acetic acid molecules and many ions.
a large number of acetic acid molecules and few ions.
a large number of acetic acid molecules and few ions.
An acid is added to water and the conductivity of the solution is high. From this observation, we conclude that the acid is:
weak and ionizes significantly.
weak, and does NOT ionize significantly.
strong, and does NOT ionize significantly.
strong and ionizes significantly.
strong and ionizes significantly.
A solution has a [H3O+] = 101 M at 250C. From this information, we conclude that the:
pH = 0 and the pOH = 14
pH = 1 and the pOH = 13
pH = -1 and the pOH = 15
pH = -1 and the pOH = 14
pH = -1 and the pOH = 15
Which statement best describes this equation:
HA + XOH → H2O + A- + X+
An acid, HA, plus a base, XOH, gives a salt plus water.
An acid, HA, plus a base, HOH, gives a salt plus water.
An acid, HA, plus a base, XOH, gives an acid plus water.
An acid, XOH, plus a base, HA, gives a salt plus water.
An acid, HA, plus a base, XOH, gives a salt plus water.
At 25oC, Kw is equal to:
1 x 10-14
1 x 1014
1 x 10-7
1 x 107
1 x 10-14
At 25oC, if [OH-] = 10-4 M, [H3O+] would then equal:
10-4 M
10-10 M
10-7 M
1010 M
10-10 M
The pH of a solution of 0.21 M NaOH is:
7
- 32
- 678
14
13.32
Consider this equilibrium:
H2O (l) + NH3 (aq) ↔ OH- (aq) + NH4+ (aq)
Which statement is correct?
Ammonia and ammonium ion are acting as acids.
Hydroxide ion is the only species acting as an acid.
Water and ammonium ion are acting as acids.
Water and ammonia are acting as bases.
Water and ammonium ion are acting as acids.
Which statement about water is true?
The conjugate acid of water is water ion and the conjugate base of water is water ion.
The conjugate acid of water is hydronium ion and the conjugate base of water is hydroxide ion.
none of these
The conjugate acid of water is hydroxide ion and the conjugate base of water is hydronium ion.
The conjugate acid of water is hydronium ion and the conjugate base of water is hydroxide ion.
The letter “p”, as in pH, is short-hand notation for:
-log10
log10
[OH-]
[H3O+]
-log10
Consider this equilibrium:
H2O (l) + NH3 (aq) ↔ OH- (aq) + NH4+ (aq)
Which statement is correct?
The conjugate acid of water is hydroxide ion and the conjugate acid of ammonia is ammonium ion.
The conjugate base of water is ammonia and the conjugate acid of ammonia is ammonium ion.
The conjugate base of water is hydroxide ion and the conjugate acid of ammonia is ammonium ion.
The conjugate base of water is hydroxide ion and the conjugate base of ammonia is ammonium ion.
The conjugate base of water is hydroxide ion and the conjugate acid of ammonia is ammonium ion.
The conjugate acids of OH-, HCO3-, and NH3 would be, respectively:
HO, HCO3 and NH4+
HO, HCO and NH4
O2-, CO32-, NH2-
H2O, H2CO3 and NH4+
H2O, H2CO3 and NH4+
Consider this reaction:
HA + H20 ↔ H3O+ + A-
Considering both directions in this equilibrium, the acids are:
HA and H3O+
H3O+ only
H2O
HA only
HA and H3O+
Which statement about water is true?
Water can act as an acid only.
Water can act as both an acid and a base to itself.
none of these
Water can act as a base only.
Water can act as both an acid and a base to itself.
Consider this reaction:
HA + H20 ↔ H3O+ + A-
Considering both directions in this equilibrium, the bases are:
HA only
H2O and A-
H3O+ only
HA and H3O+
H2O and A-
For the equation:
H2O + NaOH → Na+ (aq) + OH- (aq)
The equation describes:
an acid-base reaction.
a neutralization reaction.
the dissolution of sodium hydroxide in water.
a titration reaction.
the dissolution of sodium hydroxide in water.
For the equation:
HA + H2O → H3O+ + A-
Which is completely true?
This is the general equation for the dissolution of an acid in water. Water is acting as an acid.
This is the general equation for all acid-base reactions.
none of these
This is the general equation for the dissolution of an acid in water. Water is acting as a base.
This is the general equation for the dissolution of an acid in water. Water is acting as a base.
For the equation:
HCl + NH3 → NH4+ + Cl-
Which statement is correct?
NH3 is the base, a salt is formed.
NH3 is the acid, a salt is formed.
NH3 is the base, no salt is formed.
HCl is the base, a salt is formed.
NH3 is the base, a salt is formed.
The pKw at 25oC is:
1 x 10-14
14
1 x 10-7
7
14
Hydrochloric acid (as strong acid) is added to water. You would expect that the equilibrium constant for this reaction to be:
none of these
a very small number.
equal to one.
a very large number.
a very large number.
If the pH is 4 at 25oC, the pOH is
7
10
2
14
10
A solution has a [H3O+] = 101 M at 250C. From this information, we conclude that the:
pH = -1 and the pOH = 15
pH = -1 and the pOH = 14
pH = 1 and the pOH = 13
pH = 0 and the pOH = 14
pH = -1 and the pOH = 15
