How many atoms does aluminum chloride contain?

 



Exercises for setting up reaction equations

When setting up reaction equations in chemistry (8th grade curriculum), you should follow these steps:


Reaction of an element of III. Main group with a halogen    

Example:
Aluminum and chlorine react to form aluminum chloride

1)Establish word equation.
 Aluminum + chlorine Aluminum chloride

2)Use symbols and formulas
  Important: Note that all gaseous elements (except noble gases) occur as diatomic elements !!


Al + Cl2 AlCl3

3) Establish reaction equation
 

 Important: The number of atoms of an element must be the same on the left and right side of the reaction arrow.


Note:Cl2 means that 2 atoms are bound in a molecule
2 AlCl3 means that 2 moles of AlCl3 are present.
Note: In a chemical reaction, it is not the atoms that change; the atoms are simply linked to one another in a different way. (see Dalton's atomic theory)

It is said: 2 moles of aluminum react with 3 moles of chlorine to form 2 moles of aluminum chloride

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