Chemistry: Acid & Bases
Examples of Electrolytes
NaCl, HNO3, HCLO3, CaCl2, KNO3, NaOH, H2SO4, NaC2H3O2, MgOH
Acidic Solution
A solution in which [H+] is greater than [OH-]
Basic Solution
A solution in which [H+] is less than [OH-]
How is pH used to classify a solution as neutral, acidic, or basic?
A solution with a pH less than 7.0 is acidic. A solution with a pH of 7.0 is neutral. A solution with a pH greater than 7.o is basic.
Lewis Acid
A substance that can accept a pair of electrons to form a covalent bond
Amphoteric
A substance that can act as either an acid or a base
Lewis Base
A substance that can donate a pair of electrons to form a covalent bond
How did Arrhenius define an acid and a base?
According to Arrhenius, acids are hydrogen-containing compounds that ionize to yield hydrogen ions (H+) in aqueous solutions. Bases are compounds that ionize to yield hydroxide ions (OH-) in aqueous solutions.
How did Lewis define an acid and a base?
According to Lewis, an acid accepts a pair of electrons and a base donates a pair of electrons during a reaction.
What distinguishes an acid from a base in the Bronsted-Lowry theory?
According to the Bronsted-Lowry theory, an acid is a hydrogen-ion donor and a base is a hydrogen-ion acceptor
How are acids and bases classified as either strong or weak?
Acids and bases are classified as strong or weak based on the degree to which they ionize in water.
Neutral Solution
Any aqueous solution in which [H+] and [OH-] are equal
Strong Acid
Completely ionized in aqueous solution ex: HCL;H2SO4
Conjugate Acid-Base Pair
Consists of two ions or molecules related by the loss or gain of one hydrogen ion
Non-Electrolytes
Covalent *Liquids or gases
Strong Base
Dissociates completely into metal ions and hydroxide ions in aqueous solution
What are two methods that are used to measure pH?
Either acid-base indicators or pH meters can be used to measure pH.
How are [H+] and [OH-] related in an aqueous solution?
For aqueous solutions, the product of the hydrogen-ion concentration and the hydroxide-ion concentration equals 1.0 x 10^-14
What products form when an acid and a base react?
In general, acids and bases react to produce a salt and water.
Electrolytes
Ionic *Solids
Weak Acid
Ionizes only slightly in aqueous solution ex: CH3COOH (Ethanol)
At what point in a titration does neutralization occur?
Neutralization occurs when the number of moles of hydrogen ions is equal to the number of moles of hydroxide ions.
Weak Base
Reacts with water to form the conjugate acid of the base and hydroxide ions
Neutralization Reaction
The complete reaction of a strong acid and a strong base produces neutral solution
Conjugate Acid
The ion or molecule formed when a base gains a hydrogen ion
Conjugate Base
The ion or molecule that remains after an acid loses a hydrogen ion
Hydronium Ion (H3O+)
The ion that forms when a water molecule gains a hydrogen ion
pH
The negative logarithm of the hydrogen-ion concentration
Equivalence Point
The point at which neutralization occurs
End Point
The point at which the indicator changes color
Titration
The process of adding a measured amount of a solution of known concentration to a solution of unknown concentration
Ion-Product Constant for Water (Kw)
The product of concentration of the hydrogen ions and hydroxide ions in water
Base Dissociation Constant (Kb)
The ratio of the concentration of the conjugate acid times the concentration of the hydroxide ion to the concentration of the base
Acid Dissociation Constant (Ka)
The ration of the concentration of the dissociated form of an acid to the concentration of the undissociated form
Self-Ionization
The reaction in which water molecules produce ions
Standard Solution
The solution of known concentration
[H+]
[H+]=10^(-pH)
[OH-]
[OH-]=10^(-pOH)
pH
pH=-log[H+]
pOH
pOH=-log[OH-]