Intensive and Extensive Properties of Matter

Introduction

The matter is everything that surrounds us and engrosses space. It has different properties. These properties are defined as intensive and extensive properties of matter, in 1917 these terms were first used by the scientist Richard C. Tolman. Intensive properties do not depend upon the quantity of matter. Extensive properties rely on the quantity of the matter. Example: Milk filled in a glass or milk filled in a jug. The extensive properties like (mass, and volume) of milk vary for both the glass and jug while the intensive properties (temperature) remain the same.

What are the Intensive Properties of Matter?

Intensive properties are defined as the properties of matter that do not depend upon the size or quantity of matter. They remain the same for both small and broad sizes.

• The intensive properties do not change with the change in the quantity of matter.

• Intensive properties are temperature (Boiling and melting point), Density, Luster, Hardness, Malleability, ductility, Colour, Odour, Refractive Index, etc.

Intensive Properties

What are the Extensive Properties of Matter?

Extensive Properties are those properties of matter that depends upon the matter's size or quantity.

• It changes with the change in the size or quantity of matter.

• Extensive properties are Volume, Weight, Mass, Size, Length, Entropy, etc.

• The Ratio of extensive properties acts as intensive properties, for example,

  $$\mathrm{Mass/ Volume= Density}$$

Here the mass and volume are extensive properties, but the density is a specific property or intensive property.

Extensive Properties

Definition of Properties of Matter

The matter is everything that surrounds us and has mass and volume. It can be air, solid food, liquid drink or water, etc. According to science, matter exists in three forms: liquid, solid, and gas. The properties of a matter are traits of the element that can be measured. A matter has two different properties: physical and chemical properties.

• The physical properties of a matter help us identify a substance by its colour, appearance, elements, which it is made up, etc.

• The chemical properties are chemical changes in the matter that are irreversible.

How to Measure Physical Properties of Matter?

Physical properties are those properties that are measured without changing the identity of the substance.

• Physical properties are mass, volume, length, density, colour, odour, malleability, melting and boiling point, hardness, temperature, etc,

• Some properties are measured in one-dimensional (Length), two-dimensional (area), and three-dimensional spaces (Volume).

• These physical properties are divided into two types − intensive and extensive properties.

Extensive Properties	Intensive Properties
Mass is a measure of the weight of the matter. Measured in kilograms.	The temperature of boiling and melting point were measured in kelvin.
Volume is measured in cubic meter(m3)	Pressure force per unit of surface area, and is measured in Pascal N/m2
Size is the measure of dimensions of a matter measured in area, volume, length, etc.	The Colour and odour of matter help in the identification of objects.
Weight is measured in kilogram (Kg)	Density is measured in kilogram per meter cube Kg/m3
The energy measured in joule(J)	Viscosity is internal friction, measured in meter per sec m/s
Heat capacity is measured in joule/ Kelvin J/K.	Refractive Index is the intensity of light that passes through a medium and is measured in ratio.

The Chemical Properties of a Substance

The chemical properties of matter are the chemical composition of a matter. They are altered by the chemical change or reaction. It is irreversible. The chemical properties are the combustion of heat, chemical stability, flammability, acidity or basicity, reactivity, coordination number, toxicity, radioactivity, etc.

• Reactivity is the ability of a substance to react with other substances.

• Acidity is the ability of an element to donate a proton and form salt in presence of metals.

• Basicity is the ability of an element to accept protons and can neutralize them with acid.

• Flammability is the potential of a substance to burn, in presence of oxygen if exposed to an ignition.

• Toxicity of a substance is the potential of that substance to harm like burns, visible or invisible damage to the skin, etc. Examples are Mercury, Lead, Toxic Air pollutants, etc.

What is The Heat of Combustion?

The heat of combustion is heat or energy released when a compound undergoes complete combustion in presence of oxygen. It is also known as the calorific value of a substance.

• When hydrocarbons burn in the presence of air, they produce carbon dioxide, water, and energy. Example − Methanol is burned in the presence of air.

  $$\mathrm{CH_3 OH + O_2 → CO_2+2H_2 O\: He(890\: KJ/mol)}$$

• It is measured in Joules or Kilojoules.

• When one mole of fuel is burned completely in the presence of oxygen it releases one kilojoule of energy. It is known as molar heat of combustion He.

• It is measured by thecalorimeter.

  $$\mathrm{Energy\: release = n* ∆Hc}$$

What is Flammability?

The word ‘Flammable’ means to catch fire. Flammability is the ability of a substance to burn and ignite. On ignition, a substance can cause fire and produces smoke and harmful gases.

• The Materials are classified, stored, and transported based on their flammability.

• All liquids do not ignite as they come near an ignition source. In some liquids the liquid changes into vapours and their vapours catch fire. This point is known as the flash point.

• Example: The flash point of 70% pure ethanol 16.6^o C means it can ignite at room temperature coming near an ignition source.

Conclusion

Every matter has its traits and properties like physical and chemical properties. The physical property of a matter can’t be altered by any chemical change in substance but the chemical properties of a matter change with chemical change in substances. The physical properties are further classified into intensive and extensive properties. Extensive properties depend upon the quantity of matter and intensive properties remain the same, it does not depend upon quantity and size.

FAQs

1. What is the autoignition point in liquids?

Some Liquids have an autoignition property which means some substances catch fire under normal pressure even without any fire. Example: Pentane’s boiling point is $\mathrm{36^o C.}$ C and it auto-ignites at $\mathrm{260^o C.}$

2. What are the thermal properties of matter?

The thermal property of matter is the ability of a matter to react in presence of heat like heat capacity, thermal conductivity, Thermal stress, etc.

3. What do you mean by the calorific value?

The calorific value is the amount of heat generated from the complete combustion of a unit of substance. It is measured in KJ/Kg.

4. What is the calorific value of food?

The calorific value of food is the amount of energy a human body produces during the metabolism of food, measured in kilocalories.

5. What is the calorific value of proteins and fats?

The calorific value of proteins is around 5.65 kcal/gm, and for fats, it is 9.45 kcal/gm.