post lab discussion 3 & 4 Flashcards
ethanol is an example of what type of alcohol
primary alcohol
isopropanol is an example of what type of alcohol
secondary alcohol
tert-butanol is an example of what type of alcohol
tertiary alcohol
what is the formula of benzyl alcohol
C6H5CH2OH
what is the formula of phenol
C6H6O or C6H5OH
what type of reaction is Baeyer’s test
oxidation reaction
what is the test for baeyer’s test
unsaturated hydrocarbons or
1 degree and 2 degree alcohols
what is the reagents used for Baeyer’s reaction
Aq Potassium Permanganate (KMnO4)
what colour is the aq Potassium Permanganate
purple
what is the positive result of Baeyer’s test
disappearance of purple color in solution and formation of brown precipitate
strong/ weak oxidation of ___ alcohols using ____
strong oxidation
primary and secondary alcohols
KMnO4
what kind of reaction is jones test
oxidation reaction
what is the test for jones test
primary and secondary alcohols
what kind of test is compatible for primary and secondary alcohols
jones test
Baeyer’s test
what reagents are used for jones test
jones reagent: chromic acid (composed of K2Cr2O7 dissolved in H2SO4)
what is the color of the jones reagent
dark orange
what is the positive result for jones test
production of blue to green colored-product
in baeyer’s test, the primary alcohols products are
aldehyde or carboxylic acid
how is aldehydes formed in Baeyer’s test
by replacing 1 C-H bond by 1 C-O bond
how is carboxylic acid formed in Baeyer’s test
by replacing 2 C-H bonds by 2 C-O bonds
in baeyer’s test, the secondary alcohols products are
ketone
how is ketone formed in Baeyer’s test
by replacing 1 C-H bond by 1 C-O bond
in jones test, the secondary alcohols products are
ketone + water + intense blue to green - 2Cr2(SO4)3
in jones test, the primary alcohols products are
carboxylic acid + water + intense blue to green - 2Cr2(SO4)3
what is the test for lucas test
to distinguish the classifications of alcohols:
tertiary alcohols - fast
secondary alcohols - slow
what is the reagents used in lucas test
concentrated hydrochloric acid (HCl) and zinc chloirde (ZnCl2)
what is the positive result for lucas test
appearance of a cloudy layer or emulsion
which alcohol in the lucas test that the solution turns turbid and forms an emulsion immediately
tertiary alcohols
which alcohol in the lucas test that the solution turns turbid and forms an oily layer in three to five minutes
secondary alcohols
in lucas test, the secondary alcohols. it turns turbid and forms an ___ layer in ___ to ___ minutes
oily layer
3 to 5 min
what is the test for ferric chloride
phenol
what are the reagents used for ferric chloride test
aq iron (III) chloride (FeCl3)
what is the positive result for ferric chloride test
purple ring at the interface
what is the chemical equation of ferric chloride test
3ArOH + FeCl3 —–> Fe(OAr)3 (colored complex)
phenols can also react with
baeyer’s test
jones reagent = produce diff color
it undergo a different reaction mechanism
with that of alcohols.
phenols
it is the “pulling out” of a substance from
one phase by another phase
extraction
the term is usually used to describe the removal of a desired compound from a solid or liquid mixture using a solvent
extraction
extraction is usually used to describe the removal of a desired compound from a____ mixture using a ____
solid or liquid
solvent
what are the steps of the extraction
- shake aq solvent and organic solvent - to allow molecules to partition
- phases settle and separate with gravity
it refers to an extraction of an organic compound from one liquid phase using another liquid
liquid- liquid extraction
Liquid-liquid extraction refers to an
extraction of an ______ from one liquid phase using another ____
organic compound
liquid
it is the most commonly used device from liquid-liquid extraction
separatory funnel
in the separatory funnel, why is the mixture shaken with frequent venting
to remove the pressure
if there is H present, what reaction can occur
oxidation reaction
how to use a separatory funnel
- aq solution and extracting solvent are mixed inside
- mixture is shaken with frequent venting
- after the 2 layers have separated, the lower layer is drained into a vessel
what is extracted from the separatory funnel?
liquid with lower or higher density
higher density first then the lower density
it is physiologically active nitrogen
containing compounds that can be extracted from plants using aqueous acid
alkaloid
alkaloid can be extracted from plants using
aqueous acid
alkaloids are ___
amines
alkaloids forms_____ when treated with _____
water soluble salt
acids
what is an example of alkaloid
caffeine
it belongs to a family of naturally occurring stimulants known as xanthines
caffeiene
caffeine belongs to a family of naturally occurring stimulants known as
xanthines
caffeine has the ability to
increase alertness
reduce sleepiness
increase the ability to think
caffeine is a vasodilator that…
relexes the blood vessels
caffeine is diuretic that….
induces urination
caffeine is ____that induces urination
diuretic
caffeine is a ______ that relaxes the blood vessels
vasodilator
caffeine can be found in
beverage (coffee, tea, cocoa, choco milk, soft drinks)
tea leaves contain ….
caffeine
cellulose
pigments and chlorophylls
tannins
it is a high-molecular weight phenolic compounds.
tannins
tannins are a high-molecular weight ____ compounds.
phenolic
what is/ are water soluble?
caffeine or tannins
both
what is range melting point of caffeine
227-228 degree celcius
is caffeine weakly basic or strongly basic
weakly basic
caffeine is moderately soluble in ____ but very soluble in ____
water (22mg/ml)
boiling water (670mg/ml)
extracting caffeine
from tea leaves by
decoction
it is a halogenated organic solvent, polar but not soluble in
water
dichloromethane
dichloromethane is a ____,
polar but not ____ in
water.
halogenated organic solvent
soluble
tannins are weakly ____
acidic
tannins can be separated from caffeine by converting them to ___ using ____
water-soluble salts
sodium carbonate
what are the disadvantages of converting tannins to salts
they bcm anionic surfactants
surfactants allow water-insoluble materials to form an emulsion with H2O (emulsion may be avoided by shaking gently. not vigorously)
how to remove the emulsion
- make the aq layer highly ionic by adding sodium chloride
- centrifugation - breaking small scale emulsion
it is toxic and carcinogen
(DCM) dichloromethane
DCM is toxic thus need to ___ under the fume hood
evaporate
what is the structure of the caffeine
search it up lol
if you shake the separatory funnel too vigorously, more ___ thus making it hard to ____
emulsion
separate
what is the residue when u evaporate the DCM under the fume hood
crude caffeine
in the separatory funnel, what is the denser solvent?
that is ur DCM (an organic solvent)
why is it important to be cautious when draining the DCM
to make sure not to contaminate ur caffeine
