K2O+H2O=KOH

What, if anything, should be done to balance this chemical equation?

As is, the equation has:

Reactants:

2 K

2 O

2 H

Products:

1 K

1 O

1 H

So, we can add coefficients to balance the equation:

K2O + H2O = 2KOH

The coefficient means that there are 2 moles of KOH, and now the equation is balanced as there is 2 of everything on both sides.