What are Intensive Properties & Extensive Properties? Definition, Examples

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What are Intensive Properties & Extensive Properties? Definition, Examples

Intensive properties and extensive properties are the most interesting properties which are explained in the simplest way. There are certain characteristics to understand the physical conditions in every system.

These are mass, pressure, temperature, volume, density, color, boiling point, etc. and these all are known as properties of the system.

Let’s explore the concept!

Intensive Properties and Extensive Properties – Definition

Intensive and Extensive Properties Basics

Intensive properties and extensive properties! Let’s take any two properties from the above, mass, and temperature to explore the concept of these two properties!

  • Now, if we increase the quantity of matter, the mass will increase but the temperature will not be changed.
  • If we increase the size of the matter, the mass will increase but the temperature will remain the same.

From this, we understand that few properties depend on the size or quantity of matter and few properties don’t.

Properties of the system are classified into two categories based on how properties are changed with respect to change in system size or quantity of matters. These are, namely,

  • Intensive properties
  • Extensive properties.
intensive properties extensive properties-type
Intensive properties extensive properties type

Types of properties Intensive properties Extensive properties

Intensive Properties Definition

What are the Intensive Properties of Matter? An intensive property is defined as the properties which don’t depend on the size or the amount of the substance present in a system.

Temperature is a property that doesn’t depend on the size or the amount of matter. Hence, these properties are known as intensive properties.

intensive properties temperature examples
Intensive properties temperature examples

Extensive Properties Definition

What are the Extensive Properties of Matter? The extensive property is different from the intensive property, and it depends on the amount of matter or the size of the system.

The mass of any substance depends on the size or quantity of matter.

Say, 10 kg of rice!

If 1 kg of rice is added, the mass of rice will increase and it will become 11 kg.

Hence, this property depends on the quantity and it is a simply extensive property.

extensive properties mass basics
Extensive properties mass basics

Intensive Properties and Extensive Examples, Symbols

Let’s try to understand the examples of intensive and expensive properties by taking 5 liters of water in a bucket.

Intensive Properties Examples

Here,

  • the volume of water is 5 liters
  • we know the density of water is 1000 kg/m3
  • mass of water = volume x density = 5 kg.
intensive extensive properties examples-details
Intensive extensive properties examples-details

Now, if we add 2 kg water to the bucket, the new mass will be (5 + 2) = 7 kg. If you measure the density of water now, do you think the density of water will be changed?

No, it will not change! Hence, density doesn’t change with respect to quantity and hence it is an intensive property.

Characteristics of Intensive Properties

The intensive property of a system has the following characteristics:

  • This property is not changed with decreasing or increasing the amount of the substance.
  • It is totally independent of the amount of matter or size.
  • No change of the size, if these properties change.

Symbols of Intensive Properties

Intensive properties are symbolized by the lower case (small letters) such as:

  • Specific volume: v
  • specific kinetic energy: ke
  • Specific internal energy: u
  • Specific enthalpy: h
  • Molar specific volume,
  • Molar specific energy,
  • Molar specific kinetic energy
  • Molar specific potential energy respectively.

Extensive Properties Examples

W have added 2 kg of water in the bucket, the new mass is (5 + 2) = 7 kg. So, mass is changed with size or quantity.

Hence, mass is an extensive property example.

Characteristics of Extensive Properties

The extensive property of a system has the following characteristics:

  • An extensive property is a physical quantity that depends on the amount of matter or substance.
  • This property is totally dependent on the amount of matter or size.
  • Change of these properties happens with a change in the size of the system.

Symbols of Extensive Properties

Extensive properties are normally symbolized by the upper case (capital letters) such as:

  • Volume: V
  • Kinetic energy: KE
  • Potential energy: PE

Exceptions of Symbol

Temperature is an intensive property, but the symbol is the capital letter ‘T’. Mass is an extensive property, but the symbol is small letter ‘m’. The number of moles is extensive property but the symbol is small i.e. mol’.

These symbols are traditionally used for a long time and continue the use.

Differences Between Intensive and Extensive Properties

There are a few differences between Intensive and Extensive properties:

Sl. No.DescriptionIntensive PropertiesExtensive Properties
1BasicIt is not related to the amount of matter or substanceIt is related to the amount of matter or substance
2Whether it is dependent on amount of matter?IndependentDependent
3Whether size is changed with the change this properties?No changeYes, Changed
4Whether it can be easily identified?Yes, easily identified.Not easily, since it depends on matters
5Whether it can be Computed?DifficultEasily computed
6ExamplesPressureVolume
Difference between Intensive and Extensive properties

Note:

These two properties can be changed, measured, or observed without changing the identity of matter.

How to Identify Intensive & Extensive Property?

Take some water in a bowl, hence it is a system. The water has many properties like mass, volume, density, temperature, etc. and the same can be measure easily.

Now, if we divide this water into two containers means two systems and measure all the above values, we will see some differences.

  • If the value is not changed then it is an intensive property.
  • And if the value of any property is changed then it is an extensive property

In the above case, if we observe, we will see that mass and volume is changed due to the change in the system. Hence, volume and mass both are extensive properties.

However, density and temperature will be the same as earlier with system change and these are intensive properties.

How to Remember Intensive & Extensive Property?

Intensive properties are independent of size or quantity, simply Independent.

Hence, we can conclude, INtensive means INdependent and easy to remember. 

Extensive is simply the opposite.

Special Note

The ratio of two extensive properties is not scale-variant, and it is therefore an intensive property.

For example,

hence, the density of water or any liquid is an intensive property.

Other examples,

Intensive Property and Extensive Property List

Intensive properties List

  • specific internal energy, u
  • temperature, T
  • Specific enthalpy (h)
  • Amount of substance (mol)
  • concentration, c
  • density, ρ
  • Energy (E)
  • Entropy (S)
  • Gibbs energy (G)
  • Heat capacity (Cp)
  • viscosity
  • Helmholtz energy (A) etc.
  • chemical potential, μ
  • melting point
  • Hardness
  • Hardness
  • Magnetization
  • Luster
  • Magnetic field
  • specific rotation, α
  • Malleability
  • magnetic permeability, μ
  • Ductility
  • Solubility
  • specific volume, v
  • boiling point
  • Elasticity
  • pressure, p
  • Refractive Index
  • molality, m or b
  • Specific conductance (or electrical conductivity)
  • specific heat capacity, cp
  • standard reduction potential, E°
  • surface tension
  • thermal conductivity
  • Colour

Mathematical Example

1 kg of water boils at 100 deg. C, what will be the boiling temperature of 5kg of water?

Explanation

Melting point or freezing point or boiling point etc. are intensive properties and we know, intensive property means it doesn’t change with the amount of object.

So, the boiling point doesn’t depend on the amount of water. Hence, the boiling point will be 100 deg. C.

Extensive properties List

  • Mass (m)
  • Volume (V)
  • Length (L)
  • Energy, E
  • Internal Energy, U
  • Surface area
  • State of Matter
  • Weight
  • Number of molecules
  • Electrical charge

Mathematical Example

1 kg of water is added to 5 kg of water, what will be the total mass of water?

Explanation

Mass is an extensive property, which means it depends on the mass. Hence, 1kg of water and 5 kg of water together give 6 kg of water.

Exercise on Intensive & Extensive Property

Question

Identifying Intensive and Extensive Properties from the below list with justification,

  • Mass
  • Density

Solution

Mass: Extensive Property

I have 2 kg sugar in a big container, so, the mass of sugar is 2 kg.

Now, if we make it half and keep it into two different small containers, then each container consists of 1 kg sugar.

  • Mass of big container = 2 kg
  • Mass of big container = 1 kg

Hence, mass is changed here, so, it is an extensive property.

Density: Intensive Property

Take a big bucket of oil and measure the density. Now, take this oil and fill it into a few small buckets.

  • The density of oil in a big bucket = 850 kg/m3
  • The density of oil in a small bucket = 850 kg/m3

The density of oil in the big bucket = the density of oil in the small buckets. Hence, no change in density, now, no change means it is an intensive property.

Density, ρ

  • ρ = mass/volume
  • ρ = mass (extensive property)/volume (extensive property)
  • ρ = intensive property

Conclusion

Hence, we have learned the basics of intensive properties and extensive properties along with a lot of examples.

Further Study

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