chemistry chapter 14; acids and bases
bases and their properties
1) bitter taste 2) bases and slippery feel 3) turn red litmus paper blue
acid base defined by behavior
1) some substances-such as water can react as acids or bases either accepting or donating a proton 2) substances that can act as bases or amphoteric.
acids and their properties
1) sour taste 2) dissolve metals 3) turn blue litmus paper red
hydrochloric acid
1) used in industry to clean metals, prepare and process foods, and refine metals ores. 2) main component of stomach acid 3) helps break down food, and it kills harmful bacteria that may enter body through food 3) sour taste associated with indigestion is caused by the stomach's hydrochloric acid reflexing up into the esophagus
in healthy individuals ph is between
7.36-7.40
the arrhenius definition of a base
a base produces OH- ions in aqueous solution.
H+ (aq) and H3O+ (aq) both refer to
a hydronium ion
in a titration...
a substance in a solution of KNOWN concentration is reacted with another substance in a solution of unknown
The Brosted-Lowry Definition of Acids
according to this definition, HCl is a part of it because in solution, it donates a proton to water. this definition more clearly accounts for what happens to Hydrogen ion from an acid; it associates with a water molecule to for a hydronium ion.
water is a
acid and base in one
the bronsted-lowry definition of acids and bases
acid is a proton donor base- proton acceptor
coffee (bases) is
acid overall, but bases present in coffee-such as caffeine- impart a bitter flavor
ph less than 7
acidic solution
under the arrhenius definiton
acids and bases naturally combine to form water, neutralizing each other
reactions of acids with metal oxides
acids react with metal oxides to produce water and a dissolved salt.
water is
amphotric; can act as wither an acid or base
the Arrhenius Definition of Acids
an acid produces H+ ions in aqueous solution. HCl is a covalent compound and does not contain ions.
our aversion to taste of bases is probably
an adaptation to protect against alkaloids, organic bases found in plants.
a weak base is
analogous to a weak acid. produce OH- by accepting a proton from water, causing the water to form OH- ions
Buffers: the acid consumes
any added base, and the base consumes any added acid. buffers resists pH change.
a conjugate acid-base pair
any two substances related to each other by the transfer of a proton can be considered a conjugate acid-base pair
the arrhenius definition does not
apply to nonaqueous solvents
sodium hydroxide, potassium hydroxide, sodium bicarbonate (bases)
are used in processing petroleum and cotton, and in soap and plastic manufacturing
ph greater than 7
basic solution
you taste sour food because
because they combine with saliva in the mouth, and they produce hydrogen ions. they hydrogen ions react with protein molecules on your tongue. the protein molecules change shape, sending an electrical signal (a nerve impulse) to your brain that you experience as a sour taste.
sulfuric acid and carbonic acid are weak in
both their ionizable protons and phosphoric acid is weak in all three of its ionizable protons
sodium bicarbonate (base)
can be found in most homes as baking soda and is an active ingredient in many antacids
the arrhenius definiton of acids and bases
cannot explain why some substances act as bases even though they do not contain OH-
acetic acid is an example of a
carboxylic acid, an acid containing the COOH grouping of atoms, known as the carboxylic acid group
a strong base is one that
completely dissociates in solution
pure water is not a good
conductor of electricity because it has few charged particles
NH3 and NH4 are often referred to as a
conjugate acid-base pair, two substances related to each other by the transfer of a proton
buffers
contains significant amounts of both a weak acid and its conjugate base
carboxylic acid are in substances
derived from living organisms. citric acid, the main acid in lemon and limes, malic acid, apples, grapes, and wine
in1923 Johannes Bronsted working in Denmark, and Thomas Lowry in England
developed the concept of proton transfer in acid-base behavior independently and simultaneously
sulfuric acid is an example of a
diprotic acid, an acid that contains two ionizable protons
aluminum is one of the
few metals that dissolve in a base
bases are less common in
foods than acids because of their bitter taste
sodium hydroxide and potassium hydroxide (bases) are....
found in most chemistry labs
neutralization reactions are also called
gas evolution reactions
acids react with metals in a way that causes metals to
go into solution 1) the reaction between an acid and a metal usually produces hydrogen gas and a dissolved salt containing the metal ion
The arrhenius definition of acids and bases
hydrogen ions are highly reactive. in aqueous solution, they bond to water molecules according to the reaction.
the H3O+ ion is the
hydronium ion. in water, hydrogen ions always associate with water molecules.
acetic acid forms in
improperly stored wines
Identifying Bronsted-Lowry Acids and bases and their conjugates
in an acid-base reaction: 1) a base accepts a proton and become a conjugate acid 2) an acid donates a proton and becomes a conjugate base
representation of an acid-base titration, HCl solution
in the hydrogen solution, the Cl- ions and the H2O molecules will not be involved in the reaction and have been omitted from the representation for clarity
sulfuric acid and nitric acid are used
in the manufacture of fertilizers, explosives, dyes, and glue.
acid-base titration
in titration, a substance in a solution of KNOWN concentration is reacted with another substance in a solution of UNKNOWN concentration
NAOH is an
ionic compound and contains sodium and OH- IONS
in water, HCL
ionizes to form hydrogen and Cl- ions
sulfuric acid 9 (listed with strong acids)
is a diprotic acid that is strong in tis first ionizable protein but weak in its second ionizable proton
sodium hydroxide (base)
is the active ingredient in products such as Drano that work to unclog drains
in the reaction between HCl and H2O
is the proton donor (acid) and H2O is the proton acceptor (base)
in the reaction NH3 and H2O
is the proton donor (acid) and NH3 is the proton acceptor (base)
when NaOH is added to water
it dissociates into its component ions
NAOH is an Arrhenius base because
it produces OH- ions in solution
acids dissolve
many metals
acids dissolve
metals
sulfuric acid is contained in
most automobile batteries
sulfuric acid is the
most widely produced chemical in the U.S.
ph=7
neutral solution
when taken as an antacid, sodium bicarbonate
neutralizes stomach acid, relieving heartburn and sour stomach
self-ionization reaction of water
occurs only to a very small extent, resulting in equal and small concentrations of H3O+ and OH-
weak acids can be
organic or inorganic
when NH3 dissolves in water it
partially ionizes to form NH4+ and OH-. however only a fraction of the molecules ionize. Most molecules remain as NH3
alkaloids (bases) are often
poisonous. the active component of hemlock, for example, is the alkaloid coniine- and their bitter taste warns us against eating them
vinegar (acetic acid) means
sour wine
acids taste
sour; sour patch kids; citric acid and tartaric acid
HCl is an example of a
strong acid, one that completely ionizes in solution
molecular compounds containing an OH group
such as methanol, do not dissociate in solution and therefore do not act as bases
acid-base titration
the ay to quantify a amount of acid or base in a solution
in an acid base titration
the equivalence point, neither reactant is present in excess and both are limiting. the number of moles of the raectants are related by the reaction of stoichiometry
reactions of bases: neutralization reactions, reactions with aluminum
the most important base reactions are those in which a base neutralizes.
reactions of acids and bases: neutralization reactions
the reaction of carbonates or bicarbonates with acids produces water, gaseous carbon dioxide and salt
bases feel slippery because
they react with oils on skin to form soaplike substances. soap itself is basic.
even in pure water, water
water acts as an acid and a base with itself, a process called self-ionization
acid-base reactions generally form
water and a salt an ionic compound- that usually dissolved in the solution. the salt contains the cation from the base and the ion from the acid
hydrobromic acid reacts with magnesium oxide to form
water and magnesium bromide
HF is an example of a
weak acid, one that does not completely ionize in solution
most carboxylic acids are
weak acids
a strong acid
when HCl dissolves in water, it completely ionizes into H3O+ and Cl- ions. the solution contains no intact HCl
a weak acid
when HF dissolves in water, only a fraction of the dissolved molecules ionize into H30+ and F- ons. the solution cantinas many intact HF molecules
reactions or acids and bases: neutralization reactions
when an acid and base are mixed, hydrogen from the acid combines with the Oh- from the base from H2O
the Brosted-Lowry definition of bases
works well with bases such as NH3 that do not inherently contain OH- but still produce OH- ions but still produce OH- ions in solution. NH3 accepts protons from water