To balance the chemical equation:
a) KOH(aq) + ZnCl2(aq) -> KCl2 + ZnOH
1. Begin by counting the number of atoms of each element on both sides of the equation:
Left side: 1 K, 1 O, 1 H, 1 Zn, 2 Cl
Right side: 1 K, 2 Cl, 1 Zn, 1 O, 1 H
2. Start by balancing the elements that appear in only one reactant and one product. In this case, only K appears in both sides, so there is no need to balance it.
3. Balance the next most complex polyatomic ion, which is OH. There is one OH on the left side and one OH on the right side, so OH is already balanced.
4. Now, let's balance Cl. There are 2 Cl on the left side and only 1 Cl on the right side. Therefore, we need to place a coefficient of 2 in front of KCl on the right side to balance the Cl atoms.
5. Check the balance of all other atoms. After adding the coefficient, the equation looks like this:
KOH(aq) + ZnCl2(aq) -> 2 KCl + ZnOH
Now, all the atoms are balanced.
To write the net ionic equation, we remove the spectator ions, which are the ions that do not undergo any chemical change. In this case, the spectator ions are K+ and Cl-. The net ionic equation is:
Zn2+(aq) + 2 OH-(aq) -> Zn(OH)2(s)