What are Physical Properties?
We all know that matter is something which occupies space and has mass. Matter is defined on the basis of its properties. The properties of matter are divided into two categories which are physical properties and chemical properties. On the basis of these properties, different parameters of the matter are measured. Thus, it is important to understand the properties of matter.
In this article, we are going to discuss only the physical properties of matter, its examples, how we can measure the physical properties, the difference between physical and chemical properties, and also the types of physical properties.
Physical Properties
The properties which define the physical state of a matter are known as physical properties of that matter. For example, shape, size, and colour all are considered as the physical properties of a matter. Any change in the physical properties will lead to the change in the measurable parameters.
Examples of Physical Properties
The examples of physical properties include the following:
Mass - It is the amount of matter a substance is composed of.
Height - It defines how long an object is.
Density - It is defined as the mass per unit volume.
Volume - It is defined as the amount of space occupied by an object.
Melting Point - It is the temperature at which a solid converts into a liquid.
Boiling Point - It is the temperature at which a liquid converts into vapour.
Pressure - It is defined as the force exerted on any object.
Temperature - It is used to define the degree of hotness or coldness of any substance.
As physical properties define the physical state of a substance, they are measured by using some fundamental units and equipment. For example,
For measuring mass, a weighing machine and the unit kg are used.
For measuring height or width, a scale and the unit cm or m are used.
For measuring pressure, pressure gauges or barometer and the unit pascal are used.
For measuring temperature, the thermometer and the unit celsius or kelvin are used.
Difference Between Physical and Chemical Properties
Physical and chemical properties of matter can be differentiated on the basis of the following points:
Table: Difference between Physical and Chemical Properties
Types of Physical Properties
Physical properties are broadly divided into two categories:
Intensive Properties
Extensive Properties
Intensive Properties
Intensive properties of any matter are those physical properties that are independent of the size of the substance or the system. Intensive properties are also known as bulk properties. Most intensive properties are used to define the identity of that substance or system. Physical properties like temperature, density, hardness etc. are the intensive properties of a substance as they do not change according to the size. For example, if the size of a piece of a marble changes, its temperature, density, and hardness remain the same.
Extensive Properties
Extensive properties of any matter are those physical properties that depend on the size of that matter and are proportional to the size of the system. Physical properties such as weight, volume etc. are the extensive properties of a substance as they change according to the size. For example, if the size of a piece of a marble changes, its weight also changes.
Important Questions
1. What is the difference between extensive and intensive properties?
Ans: An extensive property could be a property that depends on the number of matter in a sample. Mass and volume are examples of extensive properties. An intensive property could be a property of matter that depends only on the kind of matter in a sample and not on the quantity.
2. Differentiate physical properties from chemical properties.
Ans: Physical Properties: Physical properties are properties that can be measured without changing the chemical composition of matter. Physical properties don't have a direct relationship to the chemical bonds of a substance. Examples for physical properties are mass, density, colour, volume, etc.
Chemical Properties: Chemical properties are properties which will be measured by changing the chemical composition of a substance. Chemical properties are measured by changing the identity of a substance. Chemical properties have a direct relationship to chemical bonds. Examples for chemical properties are reactivity of chemicals, number, coordination number, etc.
Summary
The properties which define the physical state of a matter are known as physical properties of that matter. For example, shape, size, and colour all are considered as the physical properties of a matter. As physical properties define the physical state of a substance, they are measured by using some fundamental units and equipment. Physical properties are divided into two types which are intensive properties and extensive properties.
FAQs on Physical Properties of Matter
1. What property of matter does a thermometer measure?
Expansion of matter is used for measuring the temperature. Solids expand very little, gases expand too much, thus expansion of liquid is often used to measure the temperature. A thermometer is used to measure the temperature of any object. Temperature is the physical property of matter which is used to define the degree of hotness or coldness of that matter. It can be measured in the units celsius which is denoted as oC, Fahrenheit which is denoted as oF, and kelvin which is denoted as K.
2. How does a change in physical properties affect the chemical properties of a substance?
A change in physical properties does not affect the chemical properties of a substance. This is because chemical properties can only be affected if the chemical composition of a substance such as oxidation states or reactivity is changed which cannot be done by just changing the amount or temperature of that substance. Thus, physical change affects physical properties and chemical change affects chemical properties. Physical changes result only in a change in the type (i.e., solid, liquid, gas) or appearance of a substance, however not the chemical composition of the substance.
3. Why do we measure temperature?
Measuring the temperature of the body is very important in medical studies. a number of diseases are characterised by a change in the temperature. With different diseases, the course of the illness could also be followed by measuring of temperature. Fever is the most common sort of disease-related (pathological) increase in temperature. This allows the doctor to research the effectiveness of treatments based on body temperatures. A fever may be a reaction to disease-specific stimuli. The body changes its normal body temperature to support the body’s own defence mechanisms.