
Chambre des Métiers et de l’Artisanat                                                                                          IMA  
3 
 
 
 
 
Exercice 3 (5 points) 
  
La glycérine a pour formule chimique C3H8O3.  
  
1) Donner le nom et le nombre des éléments chimiques qui composent cette molécule.  
  
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2) Calculer sa masse molaire moléculaire à l’aide des données ci-dessous.  
  
Données :  MC =  12 g/mol ;               MH = 1 g/mol ;                    MO = 16 g/mol  
  
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