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Example Questions
Example Question #3 : Molecular Structure Of Acids And Bases
Put the following acids in order of their DECREASING acid strength: HOCl, HOBr, HOI, H2O.
H2O, HOI, HOBr, HOCl
HOI, HOBr, HOCl, H2O
HOCl, H2O, HOBr, HOI
HOCl, HOBr, HOI, H2O
H2O, HOCl, HOBr, HOI
HOCl, HOBr, HOI, H2O
Acid strength of an oxy acid increases with increasing electronegativity on the halogen.
Example Question #671 : Ap Chemistry
Put the following acids in order of their DECREASING acid strength: HOCl, HO2Cl, HO3Cl, HO4Cl.
HO2Cl, HOCl, HO3Cl, HO4Cl
HO4Cl, HO3Cl, HO2Cl, HOCl
HOCL, HO2Cl, HO3Cl, HO4Cl
HO4Cl, HOCl, HO2Cl, HO3Cl
HOCl, HO4Cl, HO2Cl, HO3Cl
HOCL, HO2Cl, HO3Cl, HO4Cl
For an oxyacid, the acid strength increases as the number of oxygens increase.
Example Question #672 : Ap Chemistry
Put the following in order of INCREASING acid strength: H2Se, KH, AsH3, HBr.
KH, H2Se, AsH3, HBr
AsH3, H2Se, KH, HBr
AsH3, H2Se, HBr, KH
HBr, H2Se, AsH3, KH
KH, AsH3, H2Se, HBr
KH, AsH3, H2Se, HBr
Acid strength increases going across a period.
Example Question #1 : Ph And Pka
If you have a solution that consist of a weak monoprotic acid (HA), with a pKA of 5.3 and a pH of 3.2, what is the predominant species present?
H3O+
A-
H2A+
Equal amounts of acid and conjugate base are present.
HA
HA
Since pH < pKa the undissociated acid is the predominant form.
Example Question #2 : Ph And Pka
If you have a solution that consists of a monoprotic acid (HA), with a pKa of 4.1 and at a pH of 5.8, what is the predominant species present?
H2A+
Equal amounts of acid and conjugate base are present.
H3O+
A-
HA
A-
Since pH > pKA, the deprotonated form of the acid is predominant.
Example Question #1 : Ph And Pka
Carbonic acid as a pKa1 = 6.35 and a pKa2=10.33. If the pH is 3.52, what is the predominant species present.
CO32-
H3O+
H2CO3
Can not be determined.
HCO3-
H2CO3
Since pH < pKa1, the undissociated form of carbonic acid (H2CO3) is predominant.
Example Question #1 : Ph And Pka
Sulphurous acid (H2SO3) has a pKa1 = 1.92 and a pKa2 = 7.18, if the pH = 5.3, what is the predominant species present?
Can not be determined
H2SO3
HSO3-
SO32-
H3O+
HSO3-
Since pH > pKa1 but pH < pKa2 the predominant form is one with a single hydrogen dissociated.
Example Question #3 : Ph And Pka
Phosphoric acid has a pKa1 = 2.15, a pKa2 = 7.20, and a pKa3 = 12.35. If the pH = 13.0, what is the predominant species present?
HPO42-
Can not be determined
H3PO4
H2PO4-
PO43-
PO43-
Since pH > pKa1, pKa2, and pKa3 the predominant form of the acid is the fully deprotonated form.
Example Question #1 : P H And Poh Of Strong Acids And Bases
Which of the following is a Lewis base?
Me3B
B2H6
BF3
NH3
NH3
NH3 should be the clear correct choice, since it is the only one having a pair of electrons that are available. The rest of the answer choices are all Lewis acids.
Example Question #1 : P H And Poh Of Strong Acids And Bases
What is the defining characteristic of Bronsted-Lowry bases?
Proton (H+) donor
Proton (H+) acceptor
Dissociates in solution to give the OH– ion
Dissociates in solution to give the H+ ion
Electron pair acceptor
Proton (H+) acceptor
The definition of a Bronsted-Lowry base is a species that has the ability to gain, or accept a proton (H+). Dissociating in solution is part of the Arrhenius definition of acids and bases, and Lewis acid are electron pair acceptors.
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