Given the unbalanced equation: CaSO4 + ___AlCl3 --> Al2(SO4)3 + CaCl2 What is the coefficient of Al2(SO4)3 when the equation is completely balanced using the smallest whole-number coefficients?

3CaSO₄  + 2AlCl₃ →  Al₂(SO₄)₃   +   3CaCl₂

Explanation:

The reaction expression is given as:

        _CaSO₄  + _AlCl₃ →  _Al₂(SO₄)₃   +   _CaCl₂

To balance the reaction above, let us a mathematical approach;

         assign coefficients a, b, c and d to the species;

       aCaSO₄  + bAlCl₃ →  cAl₂(SO₄)₃   +   dCaCl₂

Conserving Ca : a  = d  

                     S:  a = 3c

                     O:  4a  = 12c

                     Al:    b = 2c

                     Cl:   3b = 2d

So;

 let a = 1, d = 1, c   = , b  =  

  Multiply by 3 through;

 a = 3, b  = 2, c  = 1 and d  = 3

  3CaSO₄  + 2AlCl₃ →  Al₂(SO₄)₃   +   3CaCl₂

the answer

explanation:

the capillary tube was too close to the bottom of the beaker.

the ruler may have moved.

water got into the capillary tube.

the temperature was not allowed to equilibrate in the 2-4 minutes.

the millers tale is the answer.