Family of Salts: An Introduction
If salts formed through the reaction of identical acids with unique bases, then all salts so formed belong to the identical family. On the other hand, if salts formed through the reaction have identical bases with unique acids, then all salts so formed have identical negative radicals, and all such salts are known to belong to the identical family.
For example: In sodium chloride and sodium sulphate, sodium that is a positive radical is identical in each of the salts. Therefore, sodium chloride and sodium sulphate belong to the sodium family. Similarly, in sodium chloride and potassium chloride, chloride that is a negative radical is identical. Thus, sodium chloride and potassium chloride each belong to the chloride family.
Classification of Salts
There are 7 types of salts in Chemistry:
1. Simple Salts
Simple salts are made of simple combinations between an acid and a base. For example, NaCl is derived from HCl (acid) and NaOH (base).
2. Neutral Salts
These salts are formed that do not contain any replaceable protons or hydroxyl ions. They have a pH of 7 and are neither acidic nor alkaline.
Examples of neutral salts:
Sodium chloride (NaCl)
Potassium chloride (KCl)
3. Acidic Salts
The reaction between a strong acid and weak base results in acidic salts. Therefore, there is an incomplete neutralisation of the acids, which results in the salts having below pH 7 and showing acidic characteristics.
Examples of acidic salt:
Ammonium sulfate ((NH4)2SO4)
Ammonium chloride (NH4Cl)
4. Basic Salts
The reaction between a strong base and a weak acid results in basic salts. Hence, there is an incomplete neutralisation of the bases and having below 7 pH that shows acidic characteristics.
Examples of basic salts:
potassium cyanide (KCN)
Zinc chloride hydroxide (Zn(OH)Cl)
5. Double Salts
Double salts have more than 1 cation or anion in their composition. Such salts are most stable in their solid form.
Example: potash alum (KAl(SO4)2·12H2O)
6. Mixed Salts
It consists of 2 anions sharing a cation or 2 cations sharing an anion. The reaction between more than 1 acid or base results in an imbalance in the number of cations or anions.
Examples of mixed salts:
Calcium disodium EDTA
Sodium potassium carbonate
7. Complex Salts
A combination of ions and molecular compounds are complex salts. It has a central metal atom surrounded by neutral molecules and charged ions.
Example: Tetra amino cupric sulfate ([Cu(NH3)4]SO4)
Family of Salts
Chloride Family: All salts have chloride as negative radicals that belong to the chloride family. For example: Sodium chloride, beryllium chloride, potassium chloride, copper chloride, calcium chloride, magnesium chloride, aluminum chloride, etc., belong to the identical family, i.e. chloride family.
Sulphate Family: All salts have sulphate ions as negative radicals, which belong to the sulphate family. For example: potassium sulphate, aluminium sulphate, copper sulphate, magnesium sulphate, sodium sulphate, etc.
Nitrate Family: All salts have nitrate ions as negative radicals belonging to the identical family, i.e. nitrate family. For example: potassium nitrate, aluminium nitrate, copper nitrate, sodium nitrate, calcium nitrate, etc.
Sodium Family: All salts have sodium ions as positive radicals that belong to the family, i.e. sodium family. For example: sodium nitrate, sodium chloride, sodium sulphate, etc.
Copper Family: All salts have copper ions as positive radicals that belong to the copper family. For example copper nitrate, copper sulphate, copper chloride, etc.
Carbonate Family: Similarly, all carbonates belong to the identical family of salt, i.e. carbonate family. For example: potassium carbonate, copper carbonate, sodium carbonate, etc.
Common Salt
Common salt is a mineral composed of sodium chloride (NaCl), a chemical compound belonging to the bigger class of salts; salt in the shape of a natural crystalline mineral is called rock salt. Common salt is a neutral salt because it is made up of sodium chloride. The open ocean has approximately 35 g (1.2 oz) of solids in step with litres of seawater, a salinity of 3.5%.
Salt is important for existence in general, and saltiness is one of the primary human tastes. Salt is one of the oldest and most ubiquitous meal seasonings, and salting is a vital technique of meal preservation. Some of the earliest proof of salt processing dates to 6,000 BC, while humans residing within present-day Romania boiled spring water to extract salts; salt-works in China date to about the same period.
Salt is used in cooking and on the table, and salt is found in many processed foods. Sodium is an important nutrient for human fitness through its function as an electrolyte and osmotic solute. Excessive salt intake can also increase the hazard of cardiovascular diseases, which includes hypertension, in kids and adults. Accordingly, several global health institutions and specialists in developed nations propose lowering the intake of famous salty foods.
Salt has become a vital source of trade and has been transported through boats throughout the Mediterranean Sea, alongside specifically constructed salt roads, and throughout the Sahara on camel caravans. The scarcity and common need for salt have led countries to battle over it and use it to elevate tax revenues.
Salt’s main industrial products are chlorine and caustic soda; salt is used in many industrial techniques, including the manufacture of polyvinyl chloride, plastics, paper pulp and many different products. Of the annual global manufacturing of approx. 100 million tons of salt, approximately 6%, is used for human intake. Others include water conditioning strategies, de-icing highways, and agricultural use.
Interesting Facts
Sodium is essential in the operation of all the signals in the cells, also to and from the brain.
Body sweat contains salt between 2.25 and 3.4 grams per litre.
Sea turtles cry to get rid of excess salt in their body because they live in the sea and sea water is saline.
Key Features
Salt is found in large quantities in seawater.
Salt is utilised in religious ceremonies and has different cultural and conventional significance.
Edible salt is bought in forms including sea salt and table salt, which generally includes an anti-caking agent and can be iodised to prevent iodine deficiency.
Salt is processed from salt mines and through the evaporation of seawater (sea salt) and mineral-rich spring water in shallow pools.
FAQs on Family of Salts
1. What defines a 'family of salts' in chemistry?
A family of salts is a group of salts that share a common positive ion (cation) or a common negative ion (anion). Salts are ionic compounds that are typically formed during a neutralisation reaction between an acid and a base.
2. How can you identify which family a salt belongs to from its chemical formula?
You can identify a salt's family by inspecting its chemical formula for a common part. For example, in the salts NaCl, KCl, and MgCl₂, the common anion is Chloride (Cl⁻), so they all belong to the chloride family. Similarly, Na₂SO₄ and K₂SO₄ belong to the sulphate family because they share the Sulphate (SO₄²⁻) anion.
3. What are some examples of common salt families as per the NCERT syllabus?
According to the CBSE syllabus for 2025-26, some important examples of salt families include:
- Sodium Salts: Sodium Chloride (NaCl), Sodium Nitrate (NaNO₃), Sodium Carbonate (Na₂CO₃). They all share the Na⁺ cation.
- Chloride Salts: Sodium Chloride (NaCl), Potassium Chloride (KCl), Calcium Chloride (CaCl₂). They all share the Cl⁻ anion.
- Sulphate Salts: Copper Sulphate (CuSO₄), Sodium Sulphate (Na₂SO₄), Magnesium Sulphate (MgSO₄). They all share the SO₄²⁻ anion.
4. How is the pH of a salt solution related to its family?
The pH of a salt solution is determined by the strength of the parent acid and base it was formed from. Salts from the same family can have similar pH values. For instance, salts in the chloride family formed from a strong acid (HCl) and a strong base (like NaOH or KOH) will create a neutral solution (pH = 7). However, a salt like Ammonium Chloride (NH₄Cl), also a chloride salt, forms an acidic solution because its parent base (NH₄OH) is weak.
5. Why is it incorrect to say that NaCl, Na₂SO₄, and K₂SO₄ all belong to one single family?
These three salts do not belong to a single family because there is no single ion common to all of them. NaCl and Na₂SO₄ belong to the sodium family (common Na⁺ ion). Na₂SO₄ and K₂SO₄ belong to the sulphate family (common SO₄²⁻ ion). A salt can belong to two different families simultaneously (one for its cation, one for its anion), but a group of salts must share the *same* ion to be classified as a single family.
6. How does the concept of a salt family relate to the neutralisation reaction that forms them?
The family of a salt is directly linked to the reactants in a neutralisation reaction. All salts belonging to the 'nitrate family' (like KNO₃, NaNO₃) are formed using Nitric Acid (HNO₃) as the parent acid. Similarly, all salts in the 'potassium family' (like KCl, K₂SO₄) are formed using a potassium base, such as Potassium Hydroxide (KOH), as the parent base.
7. What is the practical importance of understanding salt families?
Understanding salt families is crucial for predicting the chemical properties and reactions of compounds. For example, in qualitative analysis, identifying that an unknown salt belongs to the carbonate family helps predict it will release carbon dioxide gas when reacting with an acid. In agriculture, knowing a fertiliser's salt family (e.g., nitrate vs. phosphate) is essential for soil management.
8. Are all salts in the 'sodium family' neutral?
No, not necessarily. While Sodium Chloride (NaCl) is neutral, other salts in the sodium family may not be. For example, Sodium Carbonate (Na₂CO₃) is a member of the sodium family but forms a basic (alkaline) solution in water. This is because it is formed from a strong base (NaOH) and a weak acid (H₂CO₃), causing the resulting solution to have a pH greater than 7.
