Acid-Base Reactions - Online Tutor, Practice Problems & Exam Prep

Acid-base reactions involve various interactions, such as acids with hydroxide bases, neutral amines, metals, and metal oxides. These reactions typically yield water and a salt, an ionic compound. For instance, nitric acid and ammonia produce ammonium nitrate, while sulfuric acid and metals generate hydrogen gas and a corresponding salt. Understanding these patterns helps predict products in acid-base reactions, essential for grasping concepts like the acid ionization constant and neutralization reactions.

Acid-Base Reactions Concept 1

Common acid-base reactions include reactions of acids with:

• a. hydroxide bases, so OH^-,
• b. neutral amines,
• c. metals, and
• d. metal oxides.

Now, an amine is just a compound that contains nitrogen and hydrogen or carbon, nitrogen, and hydrogen. And then remember that neutral amines are weak bases. So, if we take a look here at our different types of acid-base reactions, in the first one we have acids reacting with a hydroxide base. We're going to say here, an acid and a base will produce water and a salt as a product. This salt is just an ionic compound.

Here we have an example of an acid-base reaction. Here we'd say that the H⁺ from the acid combines with the OH^- from the base to give us water as a liquid, and then Li⁺ and Br^- will combine together to give me my salt, so LiBr aqueous.

Here we have acids reacting with a neutral amine. So, neutral amines, remember, are weak bases. An example we have NH₃ which is ammonia, composed of nitrogen and hydrogen. And here we have what's called methylamine, which has carbon, nitrogen, and hydrogen involved. Here we're going to say that this acid and base together produce a salt. So here we have nitric acid reacting with ammonia. What's going to happen is you're going to create ammonium nitrate as a salt. So remember, this is an ionic compound.

Here we can have acids reacting with metals. So, the common metals can include sodium, potassium, magnesium, calcium, iron, zinc, aluminum, and tin. Here, we're going to say that our acid and metal will produce hydrogen gas, so H₂ gas, and they'll also produce a salt.

Alright. So here we have sulfuric acid reacting with a metal; we're going to produce H₂ gas, and then the iron will combine with the sulfate to give me iron(II) sulfate aqueous.

Finally, we can have an acid reacting with a metal oxide. Examples of metal oxides include lithium oxide, sodium oxide, potassium, magnesium, calcium, barium, and iron(II) oxide. Here, we're going to say the acid and the metal oxide, they're going to produce water as a product, as well as, again, a salt.

So here, we'd say that we're going to create water from these reacting, and then we'd also create iron(II) chloride. Here we're not really worrying about balancing; we're just looking to see what kind of products we're making from each of these. Remember, these are pattern recognition types of examples. You have to understand what kind of compound is the acid reacting with to help you determine the products that will form.

Acid-Base Reactions Example 1

Here it says complete the following reaction. Here we have an acid in the form of hydrofluoric acid reacting with a hydroxide base in the form of potassium hydroxide. So what's going to happen? Treat this like a regular double displacement reaction. We have sulfuric hydrochloric acid which is composed of H⁺F^-, and then we have potassium hydroxide which is K⁺OH^-. Remember, opposites attract. This positive and this negative will now attract to give me water as a liquid, and then this positive and this negative will combine to give me my salt, KF, or potassium fluoride aqueous. So this will represent the 2 products that are formed within this reaction. Here, everything's already balanced. It'd be a coefficient of 1 for each of the compounds within this equation.

Write a balanced chemical equation for the following acid-base reaction:
Bromic acid reacting with hydrazine (N₂H₄).

• A. HBrO₃ (aq) + N₂H₄ (aq) → N₂H₅BrO₃ (aq)
• B. HBrO4 (aq) + N2H4 (aq) → N₂H₅BrO₄ (aq)
• C. HBrO3 (aq) + N2H4 (aq) → H₂BrO₃ (aq) + N₂H₃^– (aq)
• D. HBrO₄ (aq) + N₂H₄ (aq) → BrO₄^– (aq) + N₂H₄⁺ (aq)

Write a balanced chemical equation, include phases, for the following acid reaction:HClO₃ reacting with Zn metal.

• A. HClO₃(aq) + Zn(l) → ZnClO₃(aq) + H(g)
• B. 2 HClO₃(aq) + Zn(l) → Zn(ClO₃)₂(aq) + 2 H(g)
• C. 2 HClO₃(aq) + 2 Zn(s) → 2 ZnClO₃(aq) + H₂(g)
• D. 2 HClO₃(aq) + Zn(s) → Zn(ClO₃)2(aq) + H₂(g)

Write a balanced chemical equation, include phases, for the following acid reaction:HBr reacting with Li₂O.

• A. 2 HBr(aq) + Li₂O(s) → H₂O(l) + 2 LiBr(aq)
• B. 2 HBr(aq) + Li₂O(s) → H₂(g) + 2 LiBrO(aq)
• C. 2 HBr(aq) + Li₂O(s) → 2 HO(aq) + 2 LiBr(aq)
• D. HBr(aq) + Li₂O(aq) → H₂O(l) + 2 LiBr(s)

Here’s what students ask on this topic:

What are the products of an acid reacting with a hydroxide base?

When an acid reacts with a hydroxide base, the products are water and a salt. This type of reaction is known as a neutralization reaction. The general equation for this reaction is:

$H_{+}+{\mathrm{OH}}_{-}\to H_{2}O$

For example, when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH), the products are water (H₂O) and sodium chloride (NaCl):

${\mathrm{HCl}}_{}+{\mathrm{NaOH}}_{}\to H_{2}O+{\mathrm{NaCl}}_{}$

How do acids react with metals?

When acids react with metals, they typically produce hydrogen gas (H₂) and a salt. The general reaction can be represented as:

${\mathrm{Acid}}_{}+{\mathrm{Metal}}_{}\to {\mathrm{Salt}}_{}+H_2\to {\mathrm{Gas}}_{}$

For example, when sulfuric acid (H₂SO₄) reacts with zinc (Zn), the products are hydrogen gas and zinc sulfate (ZnSO₄):

$H_2{\mathrm{SO}}_4+{\mathrm{Zn}}_{}\to H_2\to {\mathrm{Gas}}_{}+{\mathrm{ZnSO}}_4$

What happens when acids react with neutral amines?

When acids react with neutral amines, they produce a salt. Neutral amines are weak bases that contain nitrogen and hydrogen or carbon, nitrogen, and hydrogen. The general reaction can be represented as:

${\mathrm{Acid}}_{}+{\mathrm{Neutral}}_{\mathrm{Amines}}\to {\mathrm{Salt}}_{}$

For example, when nitric acid (HNO₃) reacts with ammonia (NH₃), the product is ammonium nitrate (NH₄NO₃):

${\mathrm{HNO}}_3+{\mathrm{NH}}_3\to {\mathrm{NH}}_4{\mathrm{NO}}_3$

What are the products of an acid reacting with a metal oxide?

When an acid reacts with a metal oxide, the products are water and a salt. The general reaction can be represented as:

${\mathrm{Acid}}_{}+{\mathrm{Metal}}_{\mathrm{Oxide}}\to {\mathrm{Salt}}_{}+H_{2}O$

For example, when hydrochloric acid (HCl) reacts with iron(II) oxide (FeO), the products are water (H₂O) and iron(II) chloride (FeCl₂):

${\mathrm{HCl}}_{}+{\mathrm{FeO}}_{}\to H_{2}O+{\mathrm{FeCl}}_2$

What is the general pattern for predicting products in acid-base reactions?

The general pattern for predicting products in acid-base reactions involves recognizing the type of compounds reacting. Here are the common patterns:

• Acid + Hydroxide Base: Produces water and a salt. Example: HCl + NaOH → H₂O + NaCl.
• Acid + Neutral Amine: Produces a salt. Example: HNO₃ + NH₃ → NH₄NO₃.
• Acid + Metal: Produces hydrogen gas and a salt. Example: H₂SO₄ + Zn → H₂ + ZnSO₄.
• Acid + Metal Oxide: Produces water and a salt. Example: HCl + FeO → H₂O + FeCl₂.

Understanding these patterns helps in predicting the products of various acid-base reactions.