Answer: <em>Upper N upper H subscript 4 superscript plus. and Upper S upper O subscript 4 superscript 2 minus.</em>
Explanation: <em>The spectator ions in this reaction are the ammonium ion and the sulfate ions.
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<em>In a reaction, not all of the ions are reacting. The ions not reacting are called the spectator ions.
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<em>When we eliminate such ions, we get an overall view of the reaction.
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<em> The reaction is:
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<em> 2NH₄⁺ + 2OH⁻ + 2H⁺ + SO₄²⁻ ⇒ 2NH₄⁺ + 2H₂O + SO₄²⁻
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<em>In ionic equations, water soluble reactants and products are split into their constituent ions while non-ionizing or gaseous reactants and products are represented as formulae or molecules.
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<em> The species that are not reacting and appears on both sides are 2NH₄⁺ and SO₄²⁻ and are the spectator ions.
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<em>These non-reactive species are eliminated from the overall ionic equation that shows the reacting ions only.</em>