notam acidul monocarboxilic saturat = CnH2nO2
100% ................................................ 31,37% O
14n+32 ............................................. 32 g O
=> n = 5
=> C4H9COOH
H3C-CH2-CH2-CH2-COOH
H3C-CH2-CH(CH3)-COOH
H3C-CH(CH3)-CH2-COOH
H3C-C(CH3)2-COOH