Question

Buna ! am si eu urmatoarea problema de chimie :
Un amestec de acetaldehida si etanol isi mareste masa prin reducere cu H2 cu 1,82%.Se cere compozitia in procente de masa si de moli a amestecului.
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Answer 1

consideram x moli de acetaldehida si ymoli etanol
Macetaldehida=MC2H4O=24+4+16=44g/mol
Metanol=MC2H6O=24+6+16=46g/mol
Reactia: CH3-CH=O(acetaldehida) + H2 -> CH3-CH2-OH (etanol)
etanolul e deja saturat, nu se mai hidrogeneaza
macetaldehida=44x si m etanol=46x
mamestecinitial=44x+46y
mamestec final=46x+46y=44x+46y+2x=mamestecinitial+2x => 2x reprezinta cresterea
44x+46y............100%
2x......................1,82%
44x+46y=200x/1,82=109,89x => 46y=65,89x => x=0,698133y
namestec=1,698133y
%acetaldehida=nacetaldehida*100/namestec=0,698133*100/1,698133=41,11
%etanol=netanol*100/namestec=58,88%
mamestec=109,89x
%acetaldehida=44x*100/109,89=40%
%etanol=65,89x*100/109,89=60%