Question

2. Calcule la formula molecular o verdadera de a partir de las siguientes formulas empíricas y pesos moleculares A. C2H5 y 58,1g a. C6H15 b. C2H5 c. C4H10 d. C H B. CH2O y 60,0 g a. CHO b. C3H2O4 c. C2H4O2 d. CH2O C. KClO3 y 122,5 g a. KClO3 b. K2Cl2O6 c. K3Cl3O9 d. K4Cl4O12

Answer 1

A. C2H5  y 58,1 g

Mm FE
C: 2 x 12 = 24 g/mol
H: 5 x 1 =      5 g/mol
````````````````````````````
           Mm = 29 g/mol

n = Mm FM
      ````````````
       Mm FE

n = 58.1 g/mol / 29 g/mol = 2
n = 2

FM: (C2H5)n = (C2H5)₂ = C₄H₁₀    RESPUESTA: C

B: CH2O y 60 g

Mm FE
C: 1 x 12 = 12 g/mol
H: 2 x 1 =      2 g/mol
O: 1 x 16 = 16 g/mol
````````````````````````````
           Mm = 30 g/mol

n = Mm FM
      ````````````
       Mm FE

n = 60 g/mol / 30 g/mol = 2
n = 2

FM: (CH₂O)n = (CH2O)₂ = C₂H₄O₂    RESPUESTA: C

C. KClO3 y 122.5 g

Mm FE
K: 1 x 39 = 39 g/mol
Cl: 1 x 35.5 = 35.5 g/mol
O:  3 x 16 =     48 g/mol
````````````````````````````
           Mm = 122.5 g/mol

n = Mm FM
      ````````````
       Mm FE

n = 122.5 g/mol / 122.5 g/mol = 1
n = 1

FM: (KClO3)n = (KClO3)₁ = KClO3   RESPUESTA: A