Experiment 9. Identification of Unknowns

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Experiment 9. Identification of Unknowns
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SOLUBILITY CLASSES
 
insol
AA
Litmus red
ether
  CA   AM   N
 
sol    
Litmus blue
 
   
sol
Litmus unchanged
                 
sol
water
  5 NaHCO3
SA
                   
sol
WA
insol
5 NaOH
insol
sol  
B  

5 HCl
sol
insol
  N
96 H2SO4
insol
  I

insol
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AA amino acids CA carboxylic acids (5 carbons
or less) AM amines (5 carbons or
less) N alcohols, aldehydes, ketones, nitriles,
amides (5 carbons or less) SA carboxylic acids,
phenols with strong electron withdrawing groups
(5 carbons or less) WA weak acids, phenols,
enols, oximes, imides, 1,3-diones, nitro
compounds B aliphatic amines, anilines N alcohols,
aldehydes esters, ketones, ethers, alkynes,
akenes I saturated hydrocarbons, haloalkanes,
aryl halides
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Unknowns 1. Carboxylic acids can be
characterized by a neutralization
equivalent 2. Amines can be characterized by a
neutralization equivalent 3. Ketones can be
characterized by a 2,4-dinitrophenyl hydrazone
derivative, oxime or related compound 4. Alcohols
can be derivatized by phenyl isocyanide
derivative, oxidation to a solid carboxylic acid
or ketone 5. Esters can be characterized by
hydrolysis if the acid or alcohol is a solid 6.
Other compounds can be characterized on the basis
of derivatives based on their likely structure.
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Department of ChemistryUniversity of
Missouri-St. LouisSolid UnknownChemistry
263 Preliminary Report FormName
________________Date ________Unknown
Number ______Physical Propertiesa)
appearanceb) melting pointc) boiling
pointe) other properties you may have
measuredSolubility Tests (use /- to indicate
positive, negative tests)H2O _____ 5NaOH,
_____ 5NaHCO3, _____ 5HCl, _____
H2SO4,_____.pH(aqueous solution) _____ .
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Department of Chemistry University of
Missouri-St. Louis Solid Unknown Chemistry
263 Preliminary Report Form Name
_____________ Date Unknown Number ______ Physi
cal Properties a) appearance b) melting
point c) boiling point e) other properties you
may have measured Solubility Tests (use /- to
indicate positive, negative tests) H2O _____
5NaOH, _____ 5NaHCO3, _____ 5HCl, _____
H2SO4,_____. pH(aqueous solution) _____ .