Oxide Reactions: Study with Video Lessons, Practice Problems & Examples

Oxides, peroxides, and superoxides from groups 1A and 2A are reactive compounds that can interact with water to form hydroxides, which are basic, or with acids to yield salts and water. For example, lithium oxide reacts with water to produce lithium hydroxide, while calcium oxide reacts with hydrochloric acid to form calcium chloride and water. This highlights the importance of understanding acid-base reactions and the formation of ionic compounds in chemical processes.

Oxide Reactions

We can say that oxides, peroxides and superoxides are groups. 1A and 2A are reactive compounds. Now they can react with water to produce hydroxides which are basic in nature and they react with acids to produce salts and water.

If we take a look here, if we have a reacting with water, we have lithium oxide reacting with liquid water, it produces lithium hydroxide base. We put a 2 here to balance it out reacting with acids. Here we have calcium oxide solid reacting with hydrochloric acid that produces our salt in the form of calcium chloride and liquid water.

To balance this we put a 2 with the hydrochloric acid. So just remember when it comes to these oxides, we can react them with water to create bases as a product or it can react them with acids to create water and an ionic compound called a salt.

Li 2 O ( s ) + H 2 O ( l ) → Li 2 OH ( aq ) Ca O ( s ) + 2 H Cl ( aq ) → Ca Cl ( aq ) + H 2 O ( l )

Oxide Reactions Example

Here it's just complete and balanced the following equation. Here we have lithium oxide reactant with hydrochloric acid. We know that when we're reacting with an acid we're going to create water and a salt.

So here lithium oxide is composed of lithium ion and the oxide ion hydrochloric acid is made-up of H plus ion and chloride ion. The lithium and chlorine chloride will combine together to give us our salt. So lithium chloride its aqueous. The oxide and the hydronium ion H combine to give us our liquid water.

To balance this, we need to put a 2 here so that both sides have two lithiums. But now we have 2 chlorines on the product side, so I put a 2 here. This here would represent our balanced overall equation between the reaction of lithium oxide solid and hydrochloric acid.

Li _ 2 O ( s ) + 2 HCl ( aq ) → 2 LiCl ( aq ) + H _ 2 O ( l )

Write a balanced equation to show what happens when strontium oxide dissolves in water.

• A. Sr₂O₃(s) + 3 H₂O(l) → 2 Sr(OH)₃(aq)
• B. SrO(s) + H₂O(l) → Sr(OH)₂(aq)
• C. SrO₂(s) + 2 H₂O(l) → Sr(OH)₄(aq)
• D. Sr₂O(s) + H₂O(l) → 2 SrOH(aq)

Write a balanced equation for the reaction of magnesium oxide with aqueous hydrochloric acid.

• A. MgO(s) + HCl(aq) → MgCl(aq) + OH(aq)
• B. MgO₂(s) + 4 HCl(aq) → MgCl₄(aq) + 2 H₂O(l)
• C. MgO(s) + 2 HCl(aq) → MgCl₂(aq) + H₂O(l)
• D. Mg₂O(s) + 2 HCl(aq) → 2 MgCl(aq) + OH(aq)

Here’s what students ask on this topic:

What are the reactions of oxides with water?

Oxides, particularly those of groups 1a and 2a, react with water to form hydroxides, which are basic in nature. For example, lithium oxide (Li₂O) reacts with water (H₂O) to produce lithium hydroxide (LiOH). The balanced chemical equation for this reaction is:

${\mathrm{Li}}_2+H_{2}O\to {\mathrm{Li}}_2\left({\mathrm{OH}}_2\right)$

This reaction produces a basic solution due to the formation of hydroxide ions (OH^-).

How do oxides react with acids?

Oxides react with acids to produce salts and water. For example, calcium oxide (CaO) reacts with hydrochloric acid (HCl) to form calcium chloride (CaCl₂) and water (H₂O). The balanced chemical equation for this reaction is:

${\mathrm{CaO}}_{+}$

This reaction produces a salt (calcium chloride) and water.

What is the difference between oxides, peroxides, and superoxides?

Oxides, peroxides, and superoxides are compounds that contain oxygen but differ in their oxygen content and bonding. Oxides contain the O^2- ion, such as in Li₂O. Peroxides contain the O₂^2- ion, such as in H₂O₂. Superoxides contain the O₂^- ion, such as in KO₂. These differences affect their reactivity and the types of reactions they undergo.

Why do oxides of groups 1a and 2a form basic solutions when reacting with water?

Oxides of groups 1a and 2a form basic solutions when reacting with water because they produce hydroxide ions (OH^-). For example, when lithium oxide (Li₂O) reacts with water, it forms lithium hydroxide (LiOH), which dissociates in water to release OH^- ions. These hydroxide ions increase the pH of the solution, making it basic. The general reaction can be represented as:

${\mathrm{MO}}_{+}$

where M represents a group 1a or 2a metal.

How do you balance chemical equations for oxide reactions?

Balancing chemical equations for oxide reactions involves ensuring that the number of atoms of each element is the same on both sides of the equation. For example, to balance the reaction of lithium oxide with water:

${\mathrm{Li}}_2+H_{2}O\to {\mathrm{Li}}_2\left({\mathrm{OH}}_2\right)$

We need to ensure that there are 2 lithium atoms, 2 oxygen atoms, and 2 hydrogen atoms on both sides. Similarly, for the reaction of calcium oxide with hydrochloric acid:

${\mathrm{CaO}}_{+}$

We balance by ensuring there are 1 calcium, 2 chlorine, and 2 hydrogen atoms on both sides.