EX2: ACIDITY AND BASICITY OF ORGANIC COMPOUNDS Flashcards
acids and bases are defined through three main concepts:
✓ Arrhenius Theory
✓ Brønsted-Lowry Theory
✓ Lewis electron pair Theory
- acid is any species that can increase the concentration of hydrogen ions (protons) in an aqueous solution
- base is any species that can increase the concentration of hydroxide ions, OH–, in an aqueous solution
ARRHENIUS THEORY
AT:
* ____ is any species that can INCREASE THE CONCENTRATION OF HYDROGEN IONS (protons) in an aqueous solution
ACID
AT:
* _____ is any species that can INCREASE THE CONC. OF HYDROXIDE IONS, OH–, in an aqueous solution
BASE
AT:
* ACID is any species that can increase the concentration of _________ (protons) in an aqueous solution
HYDROGEN IONS H+
aqueous solution
SOLVENT = WATER
AT:
* BASE is any species that can increase the concentration of ____________ in an aqueous solution
HYDROXIDE IONS OH-
hindi gumagana ang arrhenius theory sa mga ____
acid or base in gaseous phase
- an acid is any species that can donate a proton (H+)
- a acid must have a hydrogen that can dissociate as H+
- a base is any species that can accept a proton
- a base must have at least one lone pair of electron to be able to form bond with a proton
BRONSTED-LOWRY THEORY
BLT:
an ______ is any species that can DONATE a proton (H+)
ACID
BLT:
* a Brønsted-Lowry ____ must have a hydrogen that can DISSOCIATE as H+
ACID
BLT:
* a _____ is any species that can ACCEPT a proton
BASE
BLT:
* a Brønsted-Lowry ____ must have at AT LEAST ONE LONE PAIR OF ELECTRON to be able to form bond with a proton
BASE
BLT:
* an ACID is any species that can _____ a proton (H+)
DONATE
BLT:
* a Brønsted-Lowry ACID must have a hydrogen that can ________ as H+
DISSOCIATE
BLT:
* a BASE is any species that can _____ a proton
ACCEPT
BLT:
* a Brønsted-Lowry base must have __________ to be able to form bond with a proton
AT LEAST ONE LONE PAIR OF ELECTRON
a CONJUFATE ACID is a species formed after the BASE ACCEPTS A PROTON, while a CONJUGATE BASE is the species formed after an ACID DONATES ITS PROTON
BRONSTED-LOWRY THEORY
BLT:
a _______ is a species formed after the BASE ACCEPTS A PROTON
CONJUGATE ACID
BLT:
a CONJUGATE ACID is a species formed after the base _____ a proton,
ACCEPTS
BLT:
a _______ is the species formed after an ACID DONATES ITS PROTON
CONJUGATE BASE
BLT:
a CONJUGATE BASE is the species formed after an acid ______ its proton
DONATES
can act as either an acid/base
AMPHOTERIC (i.e. water)
product of acid-base reaction
conj acid & conj base
_____ react almost COMPLETELY with water
STRONGER ACIDS
react ONLY SLIGHTLY with water
WEAK ACIDS
sample of weak acid
ACETIC ACID
gives the EXACT STRENGTH of a given acid in water
Ka (acidity constant)
the NEGATIVE LOGARITH in the definition of pKa indicates an _______ between Ka and pKa
INVERSE RELATIONSHIP
the _______ in the definition of pKa indicates an INVERSE RELATIONSHIP between Ka and pKa
NEGATIVE LOGARITHM
- an acid is a species that can accept a pair of non-bonding electrons
- a base is a species that can donate a pair of non-bonding electrons
- suggest that acids react with bases, sharing a pair of electrons, with no change in the oxidation numbers of any atoms
LEWIS ELECTRON PAIR THEORY
LEPT:
* an ____ is a species that can ACCEPT a pair of non-bonding electrons
ACID
LEPT:
* an ACID is a species that can ______ a pair of non-bonding electrons
ACCEPT
LEPT:
* a _____ is a species that can DONATE a pair of non-bonding electrons
BASE
LEPT:
* a BASE is a species that can ______ a pair of non-bonding electrons
DONATE
- suggest that acids react with bases, SHARING A PAIR OF ELECTRONS, with NO CHANGE IN THE OXIDATION NUMBERS of any atoms
LEWIS ELECTRON PAIR THEORY
pH
H+ ions / acid
pOH
HYDROXIDE OH- / BASIC
defined as the NEGATIVE LOGARITHM of the H+ ion concentration of a
substance
pH
defined as the NEGATIVE LOGARITHM of the OH– ion concentration of a substance
pOH
the pH scale allows us to easily classify substances based on their acidity and basicity at
25°C
pH level of stomach acid
1
ph level of vinegar
2
ph level of orange juice
3
pH level of tomato
4
pH level of black coffee
5
pH level of urine
6
pH level of water
7
pH level of sea water
8
pH level of baking soda
9
pH level of indigestion tablet
10
pH level of ammonia soln
11
pH level of soapy water
12
pH level of bleach
13
pH level of drain cleaner
14
low pH level
aicd
high pH level
alkali / basic
neutral ph level
5 - 7
measures the pH of the solution by changing its color depending on the concentration of H+ and OH– ions
pH paper
pH paper is treated with an indicator, which is ______, an ANTHOCYANIN commonly found in red cabbages
FLAVIN
flavin is commonly found in
RED CABBAGES
flavin usually turns:
* red if the solution is
ACIDIC
flavin usually turns:
greenish if the soln is
NEUTRAL
flavin usually turns:
purple if the soln is
BASIC
- a MORE ACCURATE method than pH paper
- determines the MOLAR CONCENTRATION
- contains a PROBE that passes the electrical signals to the meter itself which interprets the electrical signals and display the results on its screen
pH METER
two electrodes that the glass pH probe contains
SENSOR ELECTRODE
REFERENCE ELECTRODE
electrode that contains a pH 7 buffer
solution
SENSOR
electrode that usually contains SATURATED POTASSIUM CHLORIDE SOLN
REFERENCE
electrodes made up of
POROUS GLASS
these electrodes made up of porous glass have both a silver wire covered with
SILVER CHLORIDE / CALOMEL
0.1 M acetic acid
ACIDIC
0.1 M acetamide
BASIC
0.1 M phenol
ACIDIC
0.1 M glycine
NEUTRAL
1% glucose
NEUTRAL
aniline
BASIC
acetone
ACIDIC TO NEUTRAL
isopropyl alcohol
ACIDIC