Question

Question #38149

Answer 1

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

Explanation:

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!