Unit 7 Acids, Bases, and Salts
how many milliliters of .45 m HCl will neutralize 25 ml of 1M KOH
56 mL
in exactly .2M solution of benzoic acid, a monoprotic acid ,the Hion=3.55X10^-3. what is the ka?
6.3X10^-5
A solution contains equal amounts of ammonia and ammonium chloride, and is buffered at a pH of 9.25. Which action will most strengthen the buffering capacity at this pH?
Double the amounts of both ammonia and ammonium chloride.
the formula of the hydrogen ion is often written as____?
H+
which of these solutions is most basic?
H+=1 X 10^-11
what are the acids in this equilibrium rxn? CN+H2O--->HCN+OH
H2O and HCN
what is the formula for phosphoric acid?
H3PO4
phosphoric acid...and it applies to the rxn described by which equation?
H3PO4=H+ + H2PO4-
which conditions apply at a pH of 7?
H=OH= 1X 10^-7
which of these is a arrhenius base?
LiOH
which of the following represents a bronsted/lowry conjugate acid base pair?
NH4+ and NH3
why might a chemist add a buffer to the solution?
The buffer can keep the pH stable when small amt of acid or base are added
in the rxn CO3^2-+H2O--->HCO3-+OH-, the carbonate ion is acting as____?
a bronsted lowry base
acetic acid ionizes in water as follows... the acetate ion is therefore____?
a good hion acceptor
what is transferred between a conjugate acid-base pair?
a hydrogen ion
for which circumstance would a buffer be most useful in a solution?
a rxn depends on a specific pH, and its products include H+
HNO3 and ammonia react to form ammonium nitrate, which is classified as____?
a salt
what is an acid according to arrhenius?
a substance that ionizes to yield H ions in an aqueous solution
sodium carbonate is formed from the rxn between____?
a weak acid and a strong base
An indicator is what type of compound?
a weak base or acid
a lewis acid is a substance that can____?
accept a pair of electrons
which pair consists of a weak acid and a strong base?
acetic acid and sodium
what characterizes a strong acid or base?
complete ionization in water
in chemistry, what is the definition of the term salt?
compounds consisting of an anion from an acid and a cation from a base.
with solutions of strong acids and strong bases, the word strong refers to____?
degree of ionization
a .12 solution of an acid that ionizes only slightly in a solution would be termed____?
dilute and weak
what type of acid is sulfuric acid?
diprotic
in a nuetral solution, the H+ is____?
equal to OH-
the adc for an acid dissolved in water is equal to the____?
equilibrium constant times the concentration of water
In a titration, when the number of moles of h+ equals the number of moles of OH+, the ____ has been reached
equivalence pt
which of the following reactions illustrates amphoterism?
h20 +h20--->H3O+OH
which acid and base will combine to form a salt without forming water?
hydrochloric acid (HCI) and ammonia (NH3)
the ionization of pure water forms____?
hydronium and hydroxide ions
what is produced when an acid reacts with water
hydronium ions
what is produced when a base reacts with water?
hydroxide ions
what is another name for the adc?
ionization constant
why does ammonia nh3 behave as a base when it reacts with and acid?
it accepts a h+ and becomes NH4
which base is strong but never concentrated?
magnesium hydroxide
which hydroxide ion yields the lowest concentration of hydroxide ions in aqueous solution?
magnesium hydroxide
which cpd could be added to hydroiodic acid(Hl) to neutralize its acidic properties?
methylamine a weak base
blood is buffered within a narrow range around a pH of 7.4 This means that the pH of blood will remain close to 7.4 when?
moderate amounts of acid or base are added
HCl and KOH react together in an aqueous solution. the rxn is and example of____?
neutralization rxn
which acid has the greatest adc?
nitric acid
nitric acid is a strong acid, and it is titrated with a standard solution of NaOH, a strong base.
pH=7
the ka of carbonic acid 4.2X10^-2 that means that H2CO3 is a____?
poor H+ donor
what kind of ion is contained in salts that produce an acidic solution?
positive ion that releases proton to water
Which salt produces the least salt hydrolysis in an aqueous solution?
potassium iodide
which is not a common property of bases?
reacts with metals
what are the products of a neutralization rxn?
salt and water
when a acid reacts with a base, which compounds are formed?
salt and water
some salts form acidic or basic solutions in water, which is a process of_____?
salt hydrolosis
which is not a property of an acid?
slippery feel
which is a property of an acid?
sour taste
when an indicator changes color in a titration, it is a sign that____?
the end pt has been reached
what is pH?
the negative logarithm of the hydrogen concentration
an acid and a base are mixed together during a titration.the equivalence pt is reached when____?
the number of moles of h+ equals the number of moles of OH+
in an acid base titration, a standard solution of 1M HCl is added to a solution of KOH. as the standard solution is added to a beaker, how does the pH change near the equivalence pt?
the pH decreases very quickly, more quickly than earlier or later in the titration
dilute hydrochloric acid is gradually added to a solution that is buffered at pH 4.76. how will the pH in the solution be affected?
the pH will initially remain close to 4.76, then will decrease quickly
the ka of HF is 6.7X10^-4. which of the following is true in a .1 Msolution of this acid?
(HF) is greater than(H)(F)
What is the molarity of phosphoric acid if 15.0 mL is completely neutralized by 38.5 mL of .150M NaOH?
.128M
A chemist adds .50 mol acetic acid ( CH3CO2H) to a solution. What else should be added to maximize the buffering effect?
.50,mol sodium acetate (NaCH3CO2)
which mixture could be a useful buffer in a solution?
.ammonia (NH3) and ammonium chloride (NH4Cl)
what is the charge of a hydronium atom?
1+
which is not a way to express the hydroxide and hydronium ion concentrations of pure water at 25C?
1.0X10^7 POSITIVE 7
the concentration of H+ in a solution is 4.5 X10^-2. What is the pH?
1.35
when the pH of a solution is 12.83 what is H+?
1.5 X 10^-13
weakest acid
10^-10
how many milliliters of 200 m h2so4 will neutralize 40.0 ml of 1.50m koh
150 mL
a chemist has a solution of sulfuric acid of an unknown concentration. to determine the concentration, the chemist should perform a titration using ____ as a standard solution
1M of NaOH
how many ionization constants are associated with oxalic acid?
2
how many moles of potassium hydroxide are needed to completely neutralize 1.56
4.68 mol KOH.
calculate the pH of a solution with OH of 4.5X10^-9?
5.65
a weak acid is titrated with a strong base. which could be the pH of the equivalence pt of the titration?
8.4
a chemist wishes to prepare a sample of AgBr. first the chemist combines hydrobromic acid(HBr) and silver hydroxide(AgOH) in an aqueous solution. which step should be followed next?
Boil away the water from the solution.
a buffering solution is made from acetic acid and its conjugate base. which rxn describes the buffering affect of the solution when an acid is added to the solution?
CH3CH2-(aq)+H+------>CH3CO2H(aq)
a buffering solution is made from acetic acid and its conjugate base. which rxn describes the buffering affect of the solution when an base is added to the solution?
CH3CO2H+ OH-------->CH3CO2+H2O
methylamine....which equals the bdc of methylamine?
CH3NH3+(OH)/CH3NH2
In the reaction of aluminum bromide with ionized sodium bromide, which compound is the Lewis acid?
aluminum bromide
which base has the smallest bdc?
ammonia
which solution could be a useful buffer in a solution
ammonia (NH3) and ammonium chloride (NH4Cl)
a solution with a ph of 8 is____?
basic
acetic acid is a weak acid, as a result, a solution of sodium acetate will be____
basic
the concentration of hydroxide ions is is 8.4 X 10^-5. this solution is____?
basic
what is the best description for a solution with a hydroxide ion concentration of 1X10^-4
basic
beaker A contains...how does the solution in beaker A compare to the solution in beaker b?
beaker a contains a more concentrated solution
which is a property of a base?
bitter taste
a base has a kb of 2.5X10^-11. which of the followign statements is true?
this base ionizes slightly
The process of adding a known amount of solution of known concentration to determine the concentration of another solution is called _____.
titration
teh process of adding a known amt of solution of known concentration to determine the concentration of another solution is called____?
titration
which food tastes acidic?
tomato
bromthymol blue is an acid-base indicator that changes color around pH7. adding a small amount of bromthymol blue to a basic solution would be most helpful in____
tracking the pH as the solution is gradually acidified
which compound can act both as a bronsted acid and bronsted base?
water
A substance with a ka of 1X10^-5 would be a____?
weak acid
the benzoate anion is the conjugate base of benzoic acid.potassium benzoate forms a basic solution in water, so benzoic acid is____?
weak acid
5 drops of 1M NaOH increase the pH of a solution from 3 to 4.6. 5 additional drops of 1 m NaOH increase the pH to 4.7. these results are evidence that the solution is buffered with____?
weak acid and conjugate base
