There seems to be a mistake. If u mistyped the 'h', then the reaction is single replacement.
Answer:
Explanation:
(NH4)3 PO4 +NaOH arrow Na3PO4 +3NH3 +3H2O
Start by seeing what happens with the Na. You need 3 on the left, so put a 3 in front of NaOH
(NH4)3 PO4 +3NaOH arrow Na3PO4 +3NH3 +3H2O Next work with the nitrogens. YOu have 3 on the left and 3 on the right, so they are OK. Next Go to the stray oxygens.
You have 3 on left in (NaOH) and three on the right in 3H2O so they are fine as well. The last thing you should look at are hydrogens.
There are 12 + 3 on the left which is 15. There are 9 (in 3NH3) and 6 more in the water. They seem fine.
Why didn't I do something with the PO4^(-3)? The reason is a deliberately stayed away from them and balanced everything else. Since they were untouched with 1 on the left and 1 on the right, they are balanced.
Species Na H O N PO4
Left 3 15 3 3 1
Right 3 15 3 3 1
