Question

Care este formula moleculara a unui compus organic care contine,in procente masice, 53,33% C, 11,11% H si masa molara 90 g/mol?

Answer 1

m(C) = m(subst) * w(C) ; m(C) = 100 * 0,75 g = 75 g m(H) = m(subst) * w(H) ; m(H) = 100 * 0,25 g = 25 g 

Answer 2

% O = 100 - 53,33 - 11,11 = 35,56
53,33/12 = 4,44
11,11/1 = 11,11
35,56/16 = 2,22
Imparti toate la 2,22 => FB = C2H5O
masa moleculara pt FB = 2*12+5+16 = 45
masa moleculara pt FM = (2*12+5+16)*n = 90 =>45n=90=>n=2
FM = C4H10O2 - formula moleculara a compusului organic