[pawesome]

Please help thanks

1)WHY ARE THE MPT OF SAMPLE 1 AND 2 DIFFERENT?
2)IDENTIFY WHICH ISOMER THE STUDENT ANALYSED

Nitration of benzene
Reacted samples of phenol with reagents
Seperated the 2 organi prod from reaction by chromatography
Suspected 2 products were structural isomers with NO2 substitudes at 2 and 4 positions

Suspected structures =
2-nitrophenol
4-nitrophenol

Measured MPT of one of products, then recrystallised sample and took MPT of recrys. product

Sample 1 = MPT before recrys. 104-108 degres
2 = MPT after recrys - 110-114 degres

MPT from databse of structural isomers = 2-nitro isomer = 44 degrees
4-nitro isomer 112 degrees

[Hunter2]

Probably water and impurities in the sample. So melting point is lower before recrystallization.  The 4-Nitrophenol was analyzed.