Question

Classify the following as Arrhenius, Bronsted-Lowry, or Lewis acid-base reactions. A reaction may fit all, two, one, or none of the categories:I. Cu2+ + 4 Cl− CuCl42−II. Al(OH)3 + 3HNO3 Al3+ + 3H2O + 3 NO3−III. N2 + 3 H2 2NH3IV. CN− + H2O HCN + OH

Answer 1

Answer:

I. Lewis acid-base reaction

II. Arrhenius, Brønsted-Lowry, and Lewis' acid-base reaction

III. Brønsted-Lowry and Lewis'acid-base reaction

IV. Lewis acid-base reaction

Explanation:

According to Arrhenius, an acid is a substance that dissolves in water to produce H+ ions, and a base is a substance that dissolves in water to produce hydroxide (OH−) ions.

In the reaction below, AH is an avid, BOH is a base reacting together to form a salt(A-B+) and water only.

AH + BOH ---> A-B+ + H2O

According to Brønsted-Lowry definition, an acid is any substance that can donate a proton, and a base is any substance that can accept a proton.

In the reaction below, AH is an acid while B is a base, reacting together to form an acid-base conjugate pair.

AH + B <-----> BH+ + A-

According to Lewis' definition, an acid is a species that accepts an electron pair while a base donates an electron pair resulting in a coordinate covalently bonded compound, also known as an adduct. In the reaction below, A+ is an acid, B- is a base, reacting together to form product A-B.

A+ + B- ------> A-B

Considering the above definitions;

I. Cu²+ + 4 Cl− ---> CuCl4²− is a Lewis acid-base reaction because it involves electron sharing only.

II. Al(OH)3 + 3HNO3 ---> Al3+ + 3H2O + 3 NO3− is an Arrhenius, Brønsted-Lowry, and a Lewis acid-base reaction because it involves protons, electrons and hydroxide ions.

III. N2 + 3 H2 ---> 2NH3 is a Lewis acid-base reaction because it involves sharing of electrons only.

IV. CN− + H2O ---> HCN + OH is both a Lewis and Brønsted-Lowry acid-base reaction because both protons and electrons sharing is involved.