Question #38149

1 Answer

The formula must be written #(NH_4)_2SO_4# because ammonium sulfate is an ionic compound.


Ionic compounds combine positively charged ions (cations) with negatively charged ions (anions).

The resulting compound will be electrically neutral - that means the compound has an overall charge of zero.

The ammonium ion (#NH_4^+#) has a charge of +1, so you need to have two of them to balance the charge of the sulfate ion (#SO_4^-2#) which has a charge of -2.

This video discusses how to determine the chemical formula for some additional examples of ternary ionic compounds. The video discusses how to write formulas for; lithium hydroxide, magnesium nitrate and aluminum sulfate.

Hope this helps!