1406 Acids-Bases Review

An Arrhenius base:

• accepts H+

• produces H+

• produces OH-

Answer explanation

Arrhenius defined bases narrowly as producing -OH ion. Bronsted and Lowry expanded the definition to include any substance that can accept a proton.

Imagine you're in a chemistry class with Samuel, Henry, and Ava. Samuel asks, "What does an Arrhenius acid do in a solution?"

• accepts H+ from another substance

• produces H+

• produces OH-

A Bronsted Lowry base:

• donates a proton to another substance

• accepts a proton from another substance

• produces H+

• produces OH-

Answer explanation

Since an H+ ion is the same thing as a proton, Arrhenius' definition of an ACID is essentially the same definition as Bronsted-Lowry's definition of an acid. However, since Bronsted-Lowry define a BASE as anything that can accept a proton, their definition includes compounds that have an N as well as hydroxides (-OH) because the N and O have a lone pair of electrons on them. That's where the proton is "accepted" (bonded).

For the following acid, what is the conjugate base?

• PO₄^3-

• H₂PO₄^-

• HPO₄^2-

• H₃PO₄

Answer explanation

Remember that a base and its conjugate acid (or an acid and its conjugate base) differ by only one proton (one H in the formula) (and the electrical charge).

For the following base, what is the conjugate acid?

• NO^-2

• NO_{2 ^-1}

• HNO₃

• H₂NO₃

For the following acid, what is the conjugate base?

• HPO₄ ^-2

• PO₄ ^-3

• H₃PO₄

Identify the Conjugate Acid.

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Answer explanation

When given a chemical equation, the conjugate acid will be the PRODUCT that has an extra H (compared to one of the reactants with which it is paired).

Identify the Conjugate Base.

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Answer explanation

When given a chemical equation, the conjugate base will be a PRODUCT that has one fewer H than the reactant with which it is paired.

Identify the base.

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Identify the acid.

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Tags

NGSS.HS-PS1-2