Notice that "po4" appears in two different places in this chemical equation. po 3−4 is a polyatomic ion called phosphate . what number should be placed in front of na3po4 to give the same total number of phosphate ions on each side of the equation? ? na3po4+mgcl2→mg3(po4)2+nacl

It can be observed from the given that at the left hand side of the chemical reaction above, there is only only phosphate ion. This can be obtain by the dissociation of Na3PO4. However, there are two phosphate ions on the right hand side of the equation by the dissociation of the Mg3(PO4)2. To equate the number of phosphate ions, we multiply Na3PO4 by 2. 

ANSWER: 2

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