Question

qucntly mode on or deductions which Tc of the compound The following Observations are frequeno in the lab. In tach case below state in belicf terms, the deduction or deducto merdes made as to the nature of the Thear study The mass spectrum of an unknown Compound Berealed on Mt fragment at m/2=121 go un nown Compound produced a branit red 2,4-dinitrophenulhudrazone whep reached with 2.4 dinitrophenylbyde an unknown solid compound gone a Meting point of 123-130°C an incrown compound cave a positive Jones test and negative test. J.) an unknown liquid compound fishy Todor not K.) A uellow solid of lodoform when the unknown was reacted with a solution of NaOH and lodine. When this unknown was burned in a spatula it left a solid residue. when this unknown was heated lin a flame, a sooty flame was observec n. When this unicnown was placed on a la copper wire and heated in a flame, a persistent greenish glow occured, Twithin tame 0.) the sodium fusion filtrate of this Tunknown gave a black precipitate when lead acetate was added.

Answer 1

f) M+ fragment - mostly belongs to benzamide

g) 2,4-DNP test gives idea of presence of aldehyde or keto functional group

h) melting point of this range suggests the presence of any one of the following compounds benzoicacid, Cinnamic acid, Maleic acid

i) Jones test is only for presence of primary or secondary alcohol or aldehyde (not for tertiary alcohol or ketone)

j) Fishy odour common for amines

k) iodoform test confirms the presence of -COCH₃ (-COCI₃)

l) saturated compounds

m) aromatic compounds - due to incomplete burning produces carbon monoxides

n)  beilstein test for presence of halides

o) Sodium fusion test - Pd(OOCCH₃)₂ + S^2-   -----> PbS (black color precipitate) - Sulphur is present

p) if unknown is positive for jone's test and negative for schiff base test then absence of aldehyde and presence of primary or secondary alcohol.

q) Optical rotation gives idea about the enantiomers (+ or -)

r) sweet smell odour is characteristic for esters

s) Negative baeyers test (KMnO₄) - indicates absence or unsaturation or no oxidizable group such as -CH₃ in toluene

t) negative for jones and positive for lucas test indicates the presence of tertiary alcohol (jones tet do not answer for 3^{0 alcohol)}