[studenthighschool]

If I was trying to balance:
H₂SO²₄ + Al³(OH)₃ --> Al³₂ (SO²₄)₃ + H₂O

When I am trying to get rid of the superscripts, I use the criss-cross method to bring down the superscript to the position of the subscript on the other side.

Would this be correct:
H₄SO₄ + Al (OH)₆ --> Al₄(SO)₆ + H₂O

Could someone please help me clarify if I am balancing equations correctly or point out the errors I have?
Thanks.

[SirRoderick]

Well for one thing H₂SO₄ is always H₂SO₄, you can't just remove and add numbers in the actual formula. You need to work with changing coëfficients.

Example

balancing C₆H₁₂O₆ + O₂ ==> H₂O + CO₂ means C₆H₁₂O₆ + 6O₂ ==> 6H₂O  + 6CO₂

[megaevelie]

The superscripts represent the charges of the elements. As you can see, every superscript of an element in a compound in the equation is the same with the subscript of the other element it is partnered with. So, disregarding the superscripts, the correct balanced equation will be:

3H2SO4 + 2Al(OH)3 --> Al2 (SO4)3 + 6H2O

Take note: when balancing equations, we do not change the subscripts. We only add coefficients before the element. The coefficient multiplied by the subscript of the element is equal to the total molecules of the element.

[megaevelie]

Step in balancing REDOX Reaction:

1. Assign the oxidation no.
2. Identify the elements that changed in oxidation number.
3. Determine increase and decrease in oxidation number, gain & loss of electron.
4. Choose the oxidizing agent, reducing agent, reduced substance and oxidized substance.
5. Make the no. of electron lost = no. of electron gained. (Choose the smallest possible multiplier)
6. Use the the multipliers as the coefficients of oxidizing agent and reducing agent and the corresponding compounds in the product.
7. Balance the equation by:
       a) Balance first the substances that underwent change in oxidation no.
       b) Balance any other atom (except H & O).
       c) Balance H & O.