Acid, bases and salt & BUFFER SYSTEM Flashcards
most common and important compounds known. In the form of aqueous solutions, these compounds are key materials in both biochemical systems and the chemical industry.
acid, bases, salts
Swedish chemist _____(1859–1927) proposed that acids and bases be defined in terms of the chemical species they form when they dissolve in water.
Svante August Arrhenius
hydrogen-containing compound that, in water, produces hydrogen ions (H+ ions). The acidic species in Arrhenius theory is thus the hydrogen ion.
Arrhenius acid
hydroxide-containing compound that, in water, produces hydroxide ions (OH- ions). The basic species in Arrhenius theory is thus the hydroxide ion. For this reason, Arrhenius bases are also called hydroxide bases
Arrhenius base
examples of arrhenius acids, This ion is formed through an interaction between water and the acid when they are mixed.
-ionization
HNO3 (nitric acid) and HCl (hydrochloric acid)
e process in which individual positive and negative ions are produced from a molecular compound that is dissolved in solution.
ionization
examples of arrhenius base, are ionic compounds in the pure state. When these compounds dissolve in water, the ions separate to yield the OH- ions.
-dissociation
NaOH (sodium hydroxide) and KOH (potassium hydroxide).
process in which individual positive and negative ions are released from an ionic compound that is dissolved in solution.
dissociation
_____(1879–1947), a Danish chemist, and ______ (1874–1936), a British chemist, independently and almost simultaneously proposed broadened definitions for acids and bases — definitions that applied in both aqueous and nonaqueous solutions and that also explained how some non hydroxide-containing substances, when added to water, produce basic solutions.
Johannes Nicolaus Brønsted and homas Martin Lowry
substance that can donate a proton (H+ ion) to some other substance.
Brønsted–Lowry acid
substance that can accept a proton (H+ ion) from some other substance.
Brønsted–Lowry base
An absolute structural requirement for a Brønsted–Lowry acid is the presence of a _____The generalized notation for a Brønsted–Lowry acid, is ___
hydrogen atom, HA
An absolute structural requirement for a Brønsted–Lowry base is the ______ of electrons. This is the site where the coordinate covalent bond forms when an incoming proton (from an acid) is accepted by the base.
presence of lone pair
a substance that can either lose or accept a proton and thus can function as either a Brønsted–Lowry acid or a Brønsted–Lowry base.
amphiprotic substance
The absolute structural requirement for an amphiprotic substance is the _____. ___ is the most common amphiprotic substance.
presence of hydrogen atom and lone pair, water
the equilibrium constant for the reaction of a weak acid with water
-It describes the likelihood of the compounds and the ions to break apart from each other.
acid ionization constant/ acid dissociation constant/ Ka
ionic equation
HCI + KOH –> H20 + KCI
H+ +CI- +K + OH- —–> H20 + K+ + CI-
ionic compound containing a metal or polyatomic ion as the positive ion and a nonmetal or polyatomic ion (except hydroxide) as the negative ion.
salt
the chemical reaction between an acid and a hydroxide base in which a salt and water are the products.
(acid + base —> water + salt
acid-base neutralization
an aqueous solution in which the concentration of H3O+ ion is higher than that of OH- ion. less than 7
acidic solution
aqueous solution in which the concentration of the OH- ion is higher than that of the H3O+ ion. greater than 7
basic solution
aqueous solution in which the concentrations of H3O+ ion and OH- ion are equal. equal to 7
neutral solution
scale of small numbers that is used to specify molar hydronium ion concentration in an aqueous solution.
pH scale (power of hydrogen)
an aqueous solution containing substances that prevent major changes in solution pH when small amounts of acid or base are added to it.
buffer
Most human body fluids are highly buffered. For example, a buffer system maintains blood’s pH at a value close to___, an optimum pH for oxygen transport.
7.4
Buffers contain two active chemical species:
(1) a substance to react with and remove added base and
(2) a substance to react with and remove added acid.
, a buffer system is composed of a weak acid and its conjugate base
a conjugate acid–base pair
contain either a weak acid and a salt of that weak acid or a weak base and a salt of that weak base.
weak acid = salt of weak acid
weak base = salt of weak base
buffer solutions
HCl and NaCl
No. An acid and the salt of that acid are present. However, the acid is a strong acid rather than a weak acid.
HCN and KCN
Yes. HCN is a weak acid, and KCN is a salt of that weak acid.
HCl and HCN
No. Both HCl and HCN are acids. No salt is present.
NaCN and KCN
No. Both NaCN and KCN are salts. No weak acid is present.
results from lower than normal levels of HCO3- ion in the blood. Causes include severe diabetes and severe diarrhea.
metabolic acidosis
results from higher than normal levels of HCO3- in the blood. This condition, less common than metabolic acidosis, can be caused by prolonged vomiting and is also a side effect of certain drugs that, like vomiting
metabolic alkalosis
results from higher than normal level of CO2 in the blood. Hypoventilation (a lowered breathing rate), caused by lung diseases such as emphysema and asthma or obstructed air passages, produces respiratory acidosis.
respiratory acidosis
results from lower than normal levels of CO2 in the blood. Causes include hysteria and anxiety (brought on, for example, by chemistry exams) and a high fever.
Respiratory alkalosis
substance whose aqueous solution conducts electricity. The presence of ions (charged particles) explains the electrical conductivity.
electrolytes
is a substance whose aqueous solution does not conduct electricity.
eg: table sugar (sucrose), glucose, and isopropyl alcohol, do not produce ions in solution.
nonelectrolyte
strong electrolytes
sodium hydroxide, sodium chloride, hydrochloric acid
weak electrolytes
acetic acid, water, ammonia
non-electrolytes
sugar, alcohol, oil
substance that completely (or almost completely) ionizes/dissociates into ions in aqueous solution.
All strong acids and strong bases and all soluble salts are strong electrolytes.
strong electrolytes
a substance that incompletely ionizes/dissociates into ions in aqueous solution.
produce solutions that are intermediate between those containing strong electrolytes and those containing nonelectrolytes in their ability to conduct an electric current.
weak electrolytes
For every kilogram of its mass, the body contains about ____mL of intracellular fluid, ____mL of interstitial fluid, and ___0 mL of blood plasma.
400, 160, 40
main component of any type of body fluid.
water
a major factor in controlling water movement, is directly related to electrolyte concentration gradients.
osmotic pressure
The electrolytes present in body fluids
(1) govern the movement of water between body fluid compartments and
(2) maintain acid–base balance within the body fluids.
essential for basic life functioning, such as maintaining electrical neutrality in cells and generating and conducting action potentials in the nerves and muscles.
electrolytes
5 signs of chemical reaction
change in color
change in odor
production of new gases
input or release of energy
difficult to reverse
number in front of reactants and products
stoichiometric coefficients
substances exist before a chemical change takes place
reactants
the new substances that are formed in chemical change
products
one in which number of atoms of each element as reactant is equal to product
balanced equation
mass relationships between substances in chemical reaction, based on mole ratio
stoichiometry
indicated by coefficients in balanced equation
mole ratio
