Question

How do bases react with the following? Write the equations. (i) non-metallic oxide (ii) ammonium salt (iii) soluble metallic salt

Short answer

Provide an example of each reaction. Answer: When a base reacts with a non-metallic oxide, it forms a salt and water. For example, calcium hydroxide (Ca(OH)₂) reacting with carbon dioxide (CO₂) forms calcium carbonate (CaCO₃) and water (H₂O). When a base reacts with an ammonium salt, it forms a corresponding salt and ammonia gas. For example, sodium hydroxide (NaOH) reacting with ammonium chloride (NH₄Cl) forms sodium chloride (NaCl) and ammonia gas (NH₃). When a base reacts with a soluble metallic salt, it forms a new salt and water. For example, potassium hydroxide (KOH) reacting with copper(II) sulfate (CuSO₄) forms potassium sulfate (K₂SO₄) and copper(II) hydroxide (Cu(OH)₂).

Step-by-step solution

Reaction with Non-metallic Oxide

When a base reacts with a non-metallic oxide, it forms a salt and water. The general equation for this kind of reaction can be written as follows: Base + Non-metallic oxide -> Salt + Water An example of this reaction is when a base like calcium hydroxide (Ca(OH)₂) reacts with carbon dioxide (CO₂), which is a non-metallic oxide. The reaction would be: Ca(OH)₂ + CO₂ -> CaCO₃ + H₂O

Reaction with Ammonium Salt

When a base reacts with an ammonium salt, it forms a corresponding salt and ammonia gas. The general equation for this type of reaction can be written as: Base + Ammonium Salt -> Salt + NH₃ (gas) An example of this reaction is when a base like sodium hydroxide (NaOH) reacts with ammonium chloride (NH₄Cl). The reaction would be: NaOH + NH₄Cl -> NaCl + NH₃ (gas)

Reaction with Soluble Metallic Salt

When a base reacts with a soluble metallic salt, it generally undergoes a double displacement reaction resulting in the formation of a new salt and water. The general equation for this type of reaction can be written as: Base + Soluble Metallic Salt -> New Salt + Water An example of this reaction is when a base like potassium hydroxide (KOH) reacts with a soluble metallic salt like copper(II) sulfate (CuSO₄). The reaction would be: 2 KOH + CuSO₄ -> K₂SO₄ + Cu(OH)₂ In summary, bases undergo different reactions with non-metallic oxides, ammonium salts, and soluble metallic salts. The resulting products include salts, water, and ammonia gas.

Key concepts

Reaction with Non-metallic Oxides

Understanding the interaction between bases and non-metallic oxides is key for students mastering the basics of acid-base chemistry. When a base encounters a non-metallic oxide, a neutralization reaction occurs, which typically results in the production of a salt and water.

The process can be represented by the generic equation:
Base + Non-metallic oxide → Salt + Water
In this reaction, the non-metallic oxide behaves similarly to an acid, even though it is not classified as such. This is because non-metallic oxides form acidic solutions when dissolved in water, thus they react with bases to produce salt and water—an outcome characteristic of acid-base neutralization.

For instance, when calcium hydroxide, which is a base, comes into contact with carbon dioxide, a classic non-metallic oxide, the products are calcium carbonate, a salt, and water:Ca(OH)₂ + CO₂ → CaCO₃ + H₂O
Key Point to Remember: Non-metallic oxides are acidic in nature and their reaction with bases resembles acid-base neutralization, creating salts and water.

Reaction with Ammonium Salts

Bases can react in intriguing ways with different substances, and ammonium salts represent a unique category in these chemical encounters. The general response of a base with an ammonium salt leads to the formation of a new salt and the release of ammonia gas.Base + Ammonium Salt → Salt + NH₃ (gas)
This reaction is essential in the world of chemistry because it releases ammonia gas, a molecule with widespread applications in agriculture, waste management, and industry.

A classic example is the reaction of sodium hydroxide, a strong base, with ammonium chloride. The result of this reaction is sodium chloride, a simple salt, and the liberation of gaseous ammonia:NaOH + NH₄Cl → NaCl + NH₃ (gas)
Education Tip: Always conduct this type of experiment in a well-ventilated space or under a fume hood because ammonia gas is irritating to the respiratory system and can be hazardous in high concentrations.

Reaction with Soluble Metallic Salts

Bases don't discriminate; they also react with soluble metallic salts. The most common result from such a reaction is the formation of a new salt and water, known as a double displacement reaction.Base + Soluble Metallic Salt → New Salt + Water
Take, for example, the reaction between potassium hydroxide (KOH), a base, and copper(II) sulfate (CuSO₄), a soluble metallic salt. This interaction yields a new salt, potassium sulfate, along with copper(II) hydroxide, which is an insoluble substance often observed precipitating out of the solution:2 KOH + CuSO₄ → K₂SO₄ + Cu(OH)₂

Application in Daily Life:

Such reactions are not just academic; they are employed in processes like water purification and waste treatment to remove heavy metals in the form of their insoluble hydroxides.

Practical Study Tip: When studying these reactions, create a chart with various bases and soluble metallic salts to visualize the different possible outcomes. This will help solidify the concept and predict the products of such reactions.