Question

I am given the following information about an unknown compound and need to answer questions A and B. Help please!

Unknown Number: 21

Physical Properties:

Solid or Liquid: Solid

Color: White Crystals

Ignition Test:

            Flammability: Non-flammable

            Manner of melting: no residue

            Odor of Gases: n/a

Bellstein Test (testing for halogens): Green flame

Melting Point: 63 ^oC

Boiling Point: n/a

Solubility :

H2O: Insoluble	5% or 10% NaOH: Soluble
5% or 10% HCl: Insoluble	5% or 10% NaHCO3: Soluble
Reactivity with H2SO4: (-) Reaction

Elemental Analysis (Sodium Fusion) :

Nitrogen: Negative	Bromine: Negative
Chlorine: Positive

A) Prediction of functional group present and reasoning why (2 reasons):

1.

2.

Narrowing your functional group.

Details as to what tests were done to narrow functional group (including whether it’s 1^o, 2^o, or 3^o as for amines/alcohols):

AgNO₃ Test - Positive

Derivative #1:

Reagent used: Thionyl chloride, aniline

Predicted derivative compound: Anilide

Predicted derivative compound melting point: 134^oC

Experimental melting point: 130-133^oC

Derivative #2:

Reagent used: Thionyl chloride

Predicted derivative compound: amide

Predicted compound melting point: 120 ^oC

Experimental melting point:

B) Name your unknown compound and reasoning for that conclusion:  

Answer 1

A) Compound 21 has Chloro group and Carboxyllic acid

1) Green colour flame  on Beilstain test indicates compound has halogen substituent and Positive test with AgNO3 confirms it and from Sodium Fusion test it is known that compound has Chloro group.

2) Compound is soluble in both NaHCO3 and 5% NaOH solution. Since it is soluble in base the compound must be acidic nature only carboxylic acids soluble in both NaOH and NaHCO3. So the compound must have Carboxylic acid functional group.

B) The name of the unknown compound 21 is monochloro Acetic acid or Chloro Acetic Acid