Answer:
Na₃PO₄ + HBr
Explanation:
To find the product of the reactants NaBr + H₃PO₄ decide what type of reaction it would likely be.
There are four elements, so it would be double displacement (where each element/polyatomic ion changes its partner). Since the reactions are not an acid (begins with H) and a base (ends with OH), it is not neutralization.
Identify what type of elements/polyatomics they are:
In NaBr, Na is metal and Br is non-metal.
In H₃PO₄, H is a metal and PO₄ is a non-metal.
Bonds only form between two non-metals, or between a non-metal and a metal; it's never metal + metal.
NaBr + H₃PO₄ => NaPO₄ + HBr
Here, the non-metals switched places to form new bonds.
Fix the number of atoms:
In each of the products, use the "criss-cross" rule, where each element has the same number of atoms as its partner's charge.
Put brackets around polyatomic ions, in this case PO₄ phosphate.
NaBr + H₃PO₄ => Na(PO₄) + HBr
Since (PO₄) has a charge of -3, which you can find on your polyatomic ions charts, its partner Na will get 3 atoms.
Since Na has a charge of +1, PO₄ gets 1 atom.
Bromide has a charge of -1, so hydrogen gets 1 atom.
NaBr + H₃PO₄ => Na₃(PO₄)₁ + H₁Br₁
Remove the brackets and any ₁ subscripts.
NaBr + H₃PO₄ => Na₃PO₄ + HBr
