Question

un acid momoaminomonocarboxilic saturat cu masa 4.45g formeaza,prin tratarea cu metanol,5.15 g de ester de metil. Care este. formula moleculara. Acestui acid

Answer 1

Intotdeauna AA monoaminomonocarboxilici, au formula generala: CnH2n+1NO2
scriem AA astfel, punand in evidenta gruparea COOH: NCn-1H2n-COOH
Maminoacid=12n+2n+1+46=14n+47g
Mester=MCn+1H2n+3NO2=12n+12+2n+3+14+32=14n+61
14n+47g......................................14n+61
NCn-1H2nCOOH + CH3OH <=> NCn-1H2nCOOCH3
4,45g............................................5,15g
5,15(14n+47)=4,45(14n+61)
72,1n+242,05=62,3n+271,45
9,8n=29,4 => n=3
C3H7NO2
aminoacidul: alfa-alanina
CH3-CH(NH2)-COOH