Common Types of Salts and Their Real-Life Applications
Salts are vital ionic compounds in chemistry, formed primarily through the neutralisation of acids and bases. Understanding the different types of salts, their properties, and real-life uses is essential for CBSE and JEE aspirants, as questions from this area are frequently asked in school and competitive exams. In this guide, you’ll learn the classification, properties, preparation, and examples of salts, along with their everyday significance.
What Is a Salt in Chemistry?
A salt is an ionic compound composed of the cation (positive ion) of a base and the anion (negative ion) of an acid. The most common method of salt formation is a neutralisation reaction between an acid and a base. For example, the reaction of sodium hydroxide (NaOH) and hydrochloric acid (HCl) forms sodium chloride (NaCl) and water:
NaOH + HCl → NaCl + H2O
Salts dissociate into ions when dissolved in water, enabling them to conduct electricity in solution. Their physical properties—such as hardness, solubility, and high melting points—arise from their orderly crystal lattice structures and strong ionic bonds.
Properties of Salts
- Generally crystalline solids with high melting and boiling points due to strong ionic bonds.
- Most are soluble in water and form electrolytic solutions.
- Exhibit different tastes—salty (NaCl), bitter (MgSO4), sour, or even sweet (lead diacetate).
- Odourless if derived from strong acids and bases, but may have characteristic odours if formed from weak acid/base (e.g., cyanide salts).
- Many are used as food additives, preservatives, medicines, and industrial chemicals.
Classification: Types of Salts in Chemistry
Salts are classified based on their method of formation, composition, or behaviour in aqueous solution. The main types include:
- Normal (Neutral) Salts: Formed by complete neutralisation of a strong acid and strong base. Their aqueous solution is neutral (pH ≈ 7).
Examples: Sodium chloride (NaCl), Potassium sulfate (K2SO4), Sodium nitrate (NaNO3). - Acidic Salts: Formed when a strong acid reacts with a weak base, or via partial neutralisation of a polyprotic acid. Their solution is acidic (pH < 7).
Examples: Ammonium chloride (NH4Cl), Sodium bisulfate (NaHSO4). - Basic Salts: Created when a strong base reacts with a weak acid, or if a polyacidic base is partially neutralised. Their solution is basic (pH > 7).
Examples: Sodium acetate (CH3COONa), Potassium cyanide (KCN). - Double Salts: Formed by the combination of two different salts crystallising together in a definite ratio. On dissolution, they dissociate into all constituent ions.
Examples: Mohr’s salt [FeSO4(NH4)2SO4·6H2O], Potash alum [K2SO4·Al2(SO4)3·24H2O]. - Complex Salts: Consist of a complex ion and simple counter ions; do not dissociate completely in solution and retain their structure.
Examples: Potassium ferrocyanide [K4[Fe(CN)6]], Hexaammine chromium(III) chloride [Cr(NH3)6]Cl3. - Mixed Salts: Contain more than one cation or anion from different acids or bases; share a common ion.
Examples: Bleaching powder (Ca(OCl)2), Sodium potassium sulfate (NaKSO4).
| Type of Salt | How Formed | Example(s) | pH of Solution |
|---|---|---|---|
| Normal (Neutral) Salt | Strong acid + Strong base | NaCl, NaNO3 | ~7 |
| Acidic Salt | Strong acid + Weak base Partial neutralisation |
NH4Cl, NaHSO4 | <7 |
| Basic Salt | Weak acid + Strong base Partial neutralisation |
CH3COONa, KCN | >7 |
| Double Salt | Two simple salts crystallised together | Mohr’s salt, Potash alum | - |
| Complex Salt | Contains a complex ion | [Cr(NH3)6]Cl3 | - |
| Mixed Salt | Two salts sharing an ion | NaKSO4, Ca(OCl)2 | - |
Common Examples and Uses of Salts
- Sodium chloride (NaCl): Table salt, food seasoning, preservative.
- Bleaching powder [Ca(OCl)2]: Used in water treatment and disinfectants.
- Washing soda (Na2CO3): Used in cleaning agents and glass manufacture.
- Potassium permanganate (KMnO4): Used as an oxidising agent and disinfectant.
- Mohr’s salt: Used in analytical chemistry as a primary standard.
Preparation Methods for Salts
- Neutralisation Reaction: Acid + Base → Salt + Water (e.g., NaOH + HCl → NaCl + H2O)
- Reaction of Metal with Acid: Metal + Acid → Salt + H2 (e.g., Zn + H2SO4 → ZnSO4 + H2)
- Direct Union: Metal + Non-metal → Salt (e.g., 2Na + Cl2 → 2NaCl)
- Acid with Carbonate: Acid + Carbonate → Salt + H2O + CO2
- Combining Acidic Oxide and Basic Oxide: e.g., CO2 + CaO → CaCO3
Real-Life and Biological Relevance
- Electrolytes: Body fluids contain various salts (e.g., Na+, K+, Cl−) essential for nerve function.
- Everyday Use: Table salt for food, washing soda for cleaning, bleaching powder for disinfection, etc.
- Industrial Use: Salts are raw materials in manufacturing chemicals, ceramics, and textiles.
Exam Significance & MCQ/Short Note Trends
- Name two basic salts and give their uses.
- Differentiate between double salt and mixed salt with examples.
- Describe the preparation of a soluble salt from a metal and an acid.
For more conceptual clarity, refer to Types Of Salts With Examples and related Vedantu links:
- Difference Between Acid Radical And Basic Radical
- Ionic Equilibrium
- Salt Hydrolysis
- Difference Between Alkali And Base
Summary
Salts are a fundamental class of compounds in chemistry, with diverse types such as neutral, acidic, basic, double, complex, and mixed salts. Their structure and formation method determine their properties and real-world applications. Mastering the classification, examples, and roles of salts is crucial for excelling in school and competitive exams alike.
FAQs on Types of Salts in Chemistry with Examples and Uses
1. What are the different types of salts with examples?
Salts are classified based on their chemical composition and reaction types. The main types are:
- Normal salts (e.g., Sodium chloride – NaCl)
- Acidic salts (e.g., Sodium bisulphate – NaHSO₄)
- Basic salts (e.g., Lead(II) chloride basic salt – Pb(OH)Cl)
- Double salts (e.g., Mohr’s salt – FeSO₄.(NH₄)₂SO₄.6H₂O)
- Complex salts (e.g., Pottasium ferrocyanide – K₄[Fe(CN)₆])
2. What is a normal salt? Give two examples.
Normal salts are formed when all replaceable hydrogen ions of an acid are replaced by metal ions or ammonium ions.
- Sodium chloride (NaCl)
- Potassium nitrate (KNO₃)
3. What is an acidic salt? Explain with examples.
Acidic salts are produced when only some of the replaceable hydrogen ions in a polybasic acid are replaced by a metal ion.
- Sodium bisulphate (NaHSO₄)
- Sodium hydrogen carbonate (NaHCO₃)
4. What are basic salts? Give suitable examples.
Basic salts are formed when a base is not fully neutralised by an acid.
- Lead(II) hydroxide chloride (Pb(OH)Cl)
- Zinc hydroxide chloride (Zn(OH)Cl)
5. Give the definition and example of double salt.
Double salts are compounds formed by the combination of two different salts crystallised together in a definite proportion.
- Mohr’s salt (FeSO₄.(NH₄)₂SO₄.6H₂O)
- Potash alum (K₂SO₄.Al₂(SO₄)₃.24H₂O)
6. What are complex salts? Provide two examples.
Complex salts contain a complex ion formed from the combination of simple ions.
- Pottasium ferrocyanide (K₄[Fe(CN)₆])
- Sodium argentocyanide (Na[Ag(CN)₂])
7. Differentiate between normal salt and acidic salt with examples.
Normal salts result from complete neutralisation, while acidic salts form from partial neutrality.
- Normal salt: NaCl – full replacement of acidic hydrogen, neutral in solution.
- Acidic salt: NaHCO₃ – partial replacement; retains one replaceable hydrogen, shows acidic properties.
8. Name some common salts used in daily life and their main uses.
Common salts and their uses include:
- Sodium chloride (NaCl): Table salt, food seasoning
- Baking soda (NaHCO₃): Cooking, antacid
- Washing soda (Na₂CO₃): Laundry, water softening
- Potassium nitrate (KNO₃): Gunpowder, fertilisers
9. What is the role of salts in our daily life?
Salts are essential for health, food, industry, and cleaning.
- Maintain electrolyte balance in the human body (NaCl)
- Used in medicines and food preservation
- Involved in cleaning agents like baking soda and washing soda
- Important for manufacturing and agriculture
10. How are salts formed? Illustrate with chemical equations.
Salts are formed by neutralisation reactions between acids and bases.
- Acid + Base → Salt + Water
- Example: HCl + NaOH → NaCl + H₂O
- Another example: H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O
11. What is the importance of studying types of salts in chemistry?
Studying the types of salts helps students understand chemical reactions, industrial processes, and daily life applications.
- Foundation for acid-base reactions
- Necessary for laboratory work
- Explains many physiological and environmental processes
- Key topic in CBSE and other science exams
12. What are basic salts with an example? (scraped)
Basic salts are those formed when a base is not fully neutralised by an acid.
- For example: Lead(II) hydroxide chloride (Pb(OH)Cl)
13. What is Mohr's salt? (scraped)
Mohr’s salt is a double salt containing ferrous sulphate and ammonium sulphate in a fixed proportion, with water of crystallisation.
- Chemical formula: FeSO₄.(NH₄)₂SO₄.6H₂O
