Here's one last equation I can't balance:

Al{subscript 2}(SO{subscript 4}){subscript 3} + ZnCl{subscript 2} -> AlCl{subscript 3} + ZnSO{subscript 4}
Please help, and thanks again.

Response
Al2(SO4)3 + 3ZnCl2 ---> 2AlCl3 + ?___ZnSO4

Why do you have "?____" before the ZnSO4?

What is your thinking? What goes in the blank?

I would guess that a 3 goes there.

The "?" before ZnSO4 indicates that we need to determine the coefficient of ZnSO4 in order to balance the equation. Balancing chemical equations involves making sure that the number of atoms of each element is the same on both sides of the equation. To determine the coefficient, we can follow these steps:

Step 1: Count the number of atoms for each element on each side of the equation.

On the left side of the equation:
Al: 2 atoms
S: 3 atoms
O: 12 atoms
Zn: 0 atoms
Cl: 6 atoms

On the right side of the equation:
Al: 2 atoms
S: 4 atoms
O: 16 atoms
Zn: ? atoms
Cl: 6 atoms

Step 2: Start with the most complex molecule (in this case, Al2(SO4)3) and balance the atoms in that molecule first.

On the left side, there are already 2 Al atoms. On the right side, there are also 2 Al atoms, so this is already balanced.

Next, balance the sulfate (SO4) ions. On the left side, there are 3 SO4 ions, while on the right side there is none. To balance this, we need to add 3 SO4 ions to the right side.

The equation now looks like this:
Al2(SO4)3 + 3ZnCl2 ---> 2AlCl3 + 3ZnSO4

Step 3: Now, let's balance the remaining atoms, Zn and Cl.

On the left side, there are 6 Cl atoms (3 from the AlCl3 and 3 from the ZnCl2), while on the right side there are 6 Cl atoms from AlCl3. This means that the Cl atoms are already balanced.

Next, count the Zn atoms. On the left side, there are 3 Zn atoms, while on the right side there is still an unknown number (represented by "?") of Zn atoms.

Step 4: Balance the Zn atoms.

Since there are 3 Zn atoms on the left side of the equation, we need to have the same number of Zn atoms on the right side. Therefore, we need to add a coefficient of 3 in front of ZnSO4.

The balanced equation is:
Al2(SO4)3 + 3ZnCl2 ---> 2AlCl3 + 3ZnSO4

Now, the equation is balanced with equal numbers of atoms on each side.