how do you balance these equations?

LiF + K2SO4 = KF + Li2(SO4)

Ba3(PO4)2 + KF = K3(PO4) + Ba2F

Ca(OH)2 + K2CO3 = K(OH) + Ca2(C)3)2

Sr(NO3)2 + Na3PO4 = Na(NO3) + Sr3(PO4)2

CaCl2 + NaI = NaCl + CaI2

OHO + MgCO3 = Mg(OH)2 + H2(CO3)
:confused:

Well, in the first ex how many Li atoms do you have on the right side versus the left? If they are not in balance, you need to adjust coefficients, or sometimes subscripts outside of brackets, to make them balance. You do this for all ions... the only thing you need to be careful of is you need to not mess with the subscripts within brackets...

For example if you need two (NO2) on one side you write (NO2)2 and NOT (N2O4)...

A simple ex -

BaCl2 + NaOH -> Ba(OH)2 + NaCl

Notice there are 2 OH's on the right, and one on the left. Not balanced. Also notice that there are 2 Cl's on the left, one on the right. Problem.

This is the balanced eq –

BaCl2 + 2NaOH -> Ba(OH)2 + 2NaCl

The coefficients in front of the NaOH and NaCl make everything work out.

Now try this with your problems and post your answers. You need to be willing to try these and fail. With practice you'll get them.

The first step is always recognizing what ions are not balanced. If you cannot seem to balance the overall eq, at least post what you think concerning what ions are not in balance.