How to balance these equations?

Question

H3PO4 + BaOH ----->

2Na2O2(s) + 2 H20 ----> 4NaOH(s) + 02(g)

16 H20 ----> 32 NaOH(s) + 8 02 (g)

NaOH(s) + 02(g) ------> Na2O2(s) + H20

CaC2(s) + H20(l) -------> C2H2(g) + Ca(OH)2(s)

CH3OCH3(g) + O2(g) -------> CO2 (g) + H20 (l)

(s) = solid, (g) = gas, (l) = liquid

Answer 1

Look Always Balance Hydrogen & Oxygen & then rest will be balanced This is golden rule of Chemistry

Answer 2

There is no BaOH.  There are three possibilities, depending on the relative amounts of acid and base.

2H3PO4(aq) + Ba(OH)2(aq) ---> Ba(H2PO4)2(s) + 2HOH(l)

H3PO4(aq) + Ba(OH)2(aq) ---> BaHPO4(s) + 2HOH(l)

2H3PO4(aq) + 3Ba(OH)2(aq) ---> Ba3(PO4)2(s) + 6HOH(l)

The coefficients in the balanced chemical equations tell the ratios of reactants needed for each reaction.