Answer
The compound in the blank is $CH_3COO^-$.
This reaction is product-favored, because this side has the weaker acid and base.
Work Step by Step
1. Identify the other compound that is next to the blank, on the same side:
- It is $HCN$;
2. Is it acting as an acid or as a base?
- As an acid, because it is donating one proton.
3. If the other compound is an acid, the blank should be a base.
4. The conjugate pair of $HCN$ is $CN^-$, therefore, the conjugate pair of the blank compound should be $CH_3COOH$.
5. Since the compound that is missing is a base, $CH_3COOH$ should be its conjugate acid.
6. Determine the conjugate base of $CH_3COOH$.
- If we remove a proton from $CH_3COOH$, it turns to $CH_3COO^-$, therefore, this is the compound in the blank.
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1. To determine which side the reaction favors, identify the side with the weaker compounds.
Acids: $HCN$ and $CH_3COOH$
- $HCN$ is weaker;
Bases: $CH_3COO^-$ and $CN^-$
- $CH_3COO^-$ is weaker.
Therefore, this reaction is product-favored.
