ShmoopTube

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And here's your Shmoop du jour, brought to you by spectators. [Man juggling balls on stage]

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Because what’s the point of doing something cool if nobody’s watching?

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Here’s today’s question.

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In the neutralization reaction between CH3 CO OH and Na OH, which of the following ions

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are spectator ions?

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And here are our potential answers.

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Well, just like the spectators at a sporting event, spectator ions are key components. [Spectators watching a sporting game]

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And just like the spectators at a sporting event, spectator ions don’t get to participate. [Ions on a football field]

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When we write out a chemical reaction, spectator ions will appear on both sides, unchanged.

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We need to examine this neutralization reaction in more detail so we can figure out who the

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spectators are.

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Unfortunately, these ones don’t identify themselves with foam fingers and face paint. [Spectator ions scribbled out]

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The first thing we need to do is identify the stronger acid or base.

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This species will dissociate completely and allow the neutralization reaction to proceed. [Acid and base stood side by side]

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You probably don’t recognize acetic acid, CH3 CO OH, as an especially strong acid,

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but hopefully you do recognize sodium hydroxide, NA OH, as a strong base. [NaOH dancing in a club]

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If not, it’d probably be a good idea to review your list of strong bases.

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Anyway, sodium hydroxide will completely dissociate in water, producing Na+ and OH-

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ions.

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The OH- will take a proton from the acid, CH3 CO OH, and the overall reaction will yield [OH- taking a proton from an acid]

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water and sodium acetate, as a salt.

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This salt will dissociate in water. [Salt poured into a beaker]

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Get all that?

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Now let’s write this reaction in terms of ions for those species that dissociate.

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So who are the spectators?

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Well, we can identify spectators based on their lack of participation in this reaction.

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The only ion that appears on both sides of the reaction, unchanged, is the sodium ion, [Sodium ions in reaction circled]

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Na+, making our answer D. Now that was well worth watching, wasn’t

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it?

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What can we say?

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We here at Shmoop like to put on a show. [People dancing in a street talent show]

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…we just hope someone will come watch our tap routine next time.

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