Filled-out chemistry worksheet featuring a classification table for acid-base theories and reaction analysis for conjugate pairs.

Problem Analysis and Solution

The worksheet focuses on identifying acids and bases using different theories (Arrhenius, Bronsted-Lowry, and Lewis) and analyzing conjugate acid-base pairs. Let's solve each section step by step.

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#### I. Identifying Acid/Base Theories

We need to determine whether each molecule or ion can act as an acid or a base according to the Arrhenius, Bronsted-Lowry, and Lewis definitions. Here is the completed table with explanations:

| Molecule/Ion | Acid or Base | Arrhenius | Bronsted-Lowry | Lewis |
|-------------------|------------------|---------------|--------------------|-----------|
| Br⁻ | base | | | X |
| CN⁻ | base | | | X |
| H₂CO₃ | acid | X | X | |
| NH₃ | base | | | X |
| HNO₂ | acid | X | X | |
| Ba(OH)₂ | base | X | | |
| HCl | acid | X | X | |
| AlCl₃ | acid | | | X |
| Cl⁻ | base | | | X |
| KOH | base | X | X | |
| IO₃⁻ | base | | | X |
| CH₃COOH | acid | X | X | |
| HNO₂ | acid | X | X | |

##### Explanation:
1. Br⁻ (Bromide Ion):
- Base: It can accept a proton (H⁺) in a Bronsted-Lowry sense.
- Lewis Base: It has lone pairs of electrons to donate.
- Not Arrhenius: It does not produce OH⁻ in water.

2. CN⁻ (Cyanide Ion):
- Base: It can accept a proton (H⁺) in a Bronsted-Lowry sense.
- Lewis Base: It has lone pairs of electrons to donate.
- Not Arrhenius: It does not produce OH⁻ in water.

3. H₂CO₃ (Carbonic Acid):
- Acid: It donates protons (H⁺) in solution.
- Arrhenius Acid: It produces H⁺ in water.
- Bronsted-Lowry Acid: It donates a proton.
- Not Lewis Acid: It does not accept electron pairs.

4. NH₃ (Ammonia):
- Base: It can accept a proton (H⁺) in a Bronsted-Lowry sense.
- Lewis Base: It has lone pairs of electrons to donate.
- Not Arrhenius: It does not produce OH⁻ in water.

5. HNO₂ (Nitrous Acid):
- Acid: It donates protons (H⁺) in solution.
- Arrhenius Acid: It produces H⁺ in water.
- Bronsted-Lowry Acid: It donates a proton.
- Not Lewis Acid: It does not accept electron pairs.

6. Ba(OH)₂ (Barium Hydroxide):
- Base: It produces OH⁻ in solution.
- Arrhenius Base: It produces OH⁻ in water.
- Not Bronsted-Lowry: It does not directly accept a proton.
- Not Lewis Base: It does not have lone pairs to donate.

7. HCl (Hydrochloric Acid):
- Acid: It donates protons (H⁺) in solution.
- Arrhenius Acid: It produces H⁺ in water.
- Bronsted-Lowry Acid: It donates a proton.
- Not Lewis Acid: It does not accept electron pairs.

8. AlCl₃ (Aluminum Chloride):
- Acid: It accepts electron pairs (Lewis acid).
- Lewis Acid: It accepts electron pairs from a base.
- Not Arrhenius/Bronsted-Lowry: It does not donate protons.

9. Cl⁻ (Chloride Ion):
- Base: It can accept a proton (H⁺) in a Bronsted-Lowry sense.
- Lewis Base: It has lone pairs of electrons to donate.
- Not Arrhenius: It does not produce OH⁻ in water.

10. KOH (Potassium Hydroxide):
- Base: It produces OH⁻ in solution.
- Arrhenius Base: It produces OH⁻ in water.
- Bronsted-Lowry Base: It accepts a proton.
- Not Lewis Base: It does not have lone pairs to donate.

11. IO₃⁻ (Iodate Ion):
- Base: It can accept a proton (H⁺) in a Bronsted-Lowry sense.
- Lewis Base: It has lone pairs of electrons to donate.
- Not Arrhenius: It does not produce OH⁻ in water.

12. CH₃COOH (Acetic Acid):
- Acid: It donates protons (H⁺) in solution.
- Arrhenius Acid: It produces H⁺ in water.
- Bronsted-Lowry Acid: It donates a proton.
- Not Lewis Acid: It does not accept electron pairs.

13. HNO₂ (Nitrous Acid):
- Acid: It donates protons (H⁺) in solution.
- Arrhenius Acid: It produces H⁺ in water.
- Bronsted-Lowry Acid: It donates a proton.
- Not Lewis Acid: It does not accept electron pairs.

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#### II. Conjugate Acids and Bases

For each reaction, we identify the acid, base, conjugate acid, and conjugate base, and determine which acid/base theory applies.

##### (a) NH₃ + H₂O → NH₄⁺ + OH⁻
- Acid: H₂O (donates a proton)
- Base: NH₃ (accepts a proton)
- Conjugate Acid: NH₄⁺
- Conjugate Base: OH⁻
- Theory: Bronsted-Lowry

##### (b) NH₄⁺ + H₂O → NH₃ + H₃O⁺
- Acid: NH₄⁺ (donates a proton)
- Base: H₂O (accepts a proton)
- Conjugate Acid: H₃O⁺
- Conjugate Base: NH₃
- Theory: Bronsted-Lowry

##### (c) 2NaOH + H₂SO₄ → 2H₂O + Na₂SO₄
- Acid: H₂SO₄ (donates protons)
- Base: NaOH (accepts protons)
- Conjugate Acid: H₂O
- Conjugate Base: SO₄²⁻
- Theory: Bronsted-Lowry, Arrhenius

##### (d) HSO₃⁻ + CN⁻ → HCN + SO₃²⁻
- Acid: HSO₃⁻ (donates a proton)
- Base: CN⁻ (accepts a proton)
- Conjugate Acid: HCN
- Conjugate Base: SO₃²⁻
- Theory: Bronsted-Lowry

##### (e) NH₂⁻ + H₂O → NH₃ + OH⁻
- Acid: H₂O (donates a proton)
- Base: NH₂⁻ (accepts a proton)
- Conjugate Acid: NH₃
- Conjugate Base: OH⁻
- Theory: Bronsted-Lowry

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#### III. Drawing Lewis Structures and Identifying the Theory

##### Reaction: AlCl₃ + Cl⁻ → AlCl₄⁻
- Lewis Structure:
- AlCl₃: Aluminum (Al) is the central atom, bonded to three chlorine (Cl) atoms.
- Cl⁻: Chloride ion has one extra electron pair.
- In the reaction, Cl⁻ donates its lone pair to AlCl₃, forming AlCl₄⁻.

- Acid/Base Theory:
- Acid: AlCl₃ (Lewis acid, accepts an electron pair)
- Base: Cl⁻ (Lewis base, donates an electron pair)
- Theory: Lewis Acid/Base Theory

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Final Answer:

\boxed{
\begin{array}{c}
\text{I. Completed Table (as explained above)} \\
\text{II. Reactions analyzed with酸/base identification and theories} \\
\text{III. Lewis structure drawn for } \text{AlCl}_3 + \text{Cl}^- \rightarrow \text{AlCl}_4^- \text{, identified as Lewis acid/base theory.}
\end{array}
}