Răspuns :

Shizuko288id

Răspuns:

1. C : 40%      :12 = 3,33    : 3,33 = 1

H : 6,66%    : 1 = 6,66    : 3,33 = 2

O : 53,33%  :16 = 3,33    : 3,33 = 1  

formula bruta  CH2O  

formula moleculara (CH2O)n    30n = 90  n = 3  

F.M. = C2H4O2

2. H% = 100- 92,31 = 7,69%

raport procente de masa se transforma in raport atomic:

C : H =  92,31/12  :  7.69/1  = 7,69  : 7,69

cea mai mica valoare imparte pe cele 2 ...deci impartim prin 7,69  si rezulta

C :  H  = 1   : 1

( CH )ₙ formula bruta.

LodovicaMid

Răspuns:

1. 40%C

6,66%H

=>O=100-40+6,66=66,66%O

M.a.=90

C:40/12=3,33

H:6,66/1=6,66

O:66,66/16=5,55

C:3,33/3,33=1

H:6,66/3,33=2

O:5,55/3,33=1,66

=>Formula bruta=C1H2O1=CH2O

=>(CHO2)n=90=>12n+1n+32n=90=>45n=90

=>n=90/45=>n=2=>Formula moleculara=(CHO2)2=C2H2O4

2. 93,31%C

=>H=100-93,31=6,69%H

C:93,31/12=7,77

H:6,69/1=6,69

C:7,77/6,69=1,16~1

H:6,69/6,669=1

=>Formula bruta=(CH)n