Question

Diga la composición porcentual de cada uno de los elementos presentes en cada sustancia:

A. Al(SO4)3
B. CaC2O4
C. H2SiO3
D. V(OH)5

Answer 1

A.    Al2(SO4)3

Mm

Al: 2 x 27 = 54 g/mol

S: 3 x 32 = 96 g/mol

O: 12 x 16 = 192 g/mol

``````````````````````````````````

         Mm = 342 g/mol

Al:

342 g --- 100 %

54 g ------  x

  x = 15.78%

S:

342 g ---- 100

96 g -----  x

 x = 28.07 %

O:

342 g ---- 100 %

192 g ----   x

   x = 56.14 %

B. CaC2O4
Ca: 1 x 40 = 40 g/mol
 C: 2 x 12 = 24 g/mol
O: 4 x 16 = 64 g/mol
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           Mm = 128 g/mol
Ca:
128 g ---- 100 %
 40 g -----    x
       x = 31.25 %
C:
128 g ---- 100 %
24 g -----    x
       x = 18.75 %
O:

128 g ---- 100 %
 64 g -----    x
       x = 50 %

C. H2SiO3
H: 2 x1 = 2 g/mol
Si: 1 x  28 = 28 g/mol
 O: 3 x 16 = 48 g/mol
``````````````````````````````
         Mm = 78 g/mol
H:
78 g ---- 100 %
 2 g -----    x
     x = 2.56 %

Si
78 g ---- 100 %
 28 g -----    x
     x = 35.89 %

 O:

78 g ---- 100 %
 48 g -----    x
     x = 61.53 %

D. V(OH)5
V. 1 x 51 = 51 g/mol
O: 5 x 16 = 80 g/mol
H: 5 x 1 = 5 g/mol
``````````````````````````
         Mm = 136 g/mol

V:
136 g ---- 100 %
  51 g ----  x
       x = 37.5 %

O:
136 g ---- 100 %
  80 g ----  x
       x =58.82 %
H:
136 g ---- 100 %
     5 g ----  x
       x =3.67 %