Question

Prin arderea in oxigen a 178 g subst org. , A , se ontin 126 g H2O, 134,4 L Co2 , si 22,4 L N2( c.n )
Se cere :
a) determina formula moleculara a substantei organice stiind ca are in molecula de doura ori mai multi atomi de oxigen decat de azot.
b) daca A este un aminoacid, scrie o formula de structura posibila a acestei substante organice si denumeste-o

Answer 1

18 g H2O...........2 g H
126 g H2O..........x
x = 14 g H
22,4 l CO2.........12 g C
134,4 l CO2........x g C
x = 72 g C
22.4 l N2...........28 g N2 => m N = 28 g
178 - 72 - 28 - 14 = 64 g oxigen
72/12 = 6
14/1 = 14
28/14 = 2
64/16 = 4
=> FM: (C3H7NO2)n
n = 1 => FM: C3H7NO2
b)CH3-CH-COOH
            NH2     
Alanina = acid 2-aminopropanoic