Table of Contents
Introduction
Surface energy quantifies the breakdown of intermolecular bonds that occur when a surface is created and it is also known as surface free energy or interfacial free energy. Simply, surface energy can be defined as the work per unit area performed by a force that creates a new surface. Drowning the ants is useless. They appear to slide across the surface of the water until they reach solid ground. But this makes no sense since the breathing mechanism is in the lower abdomen. They simply move in the same way as land, except for other maneuvering skills. They can do this due to a phenomenon known as surface tension. The cohesive forces between the liquid molecules result in the presence of thin films (layers) on the surface due to surface tension. The surface energy is the work done per unit area to create this new surface. And if the insect is light enough not to damage (brittle) the layer, the thin layer can be used as a walking support.
The information about surface energy from various physics-related articles are available here. Surface energy and its relationship with surface tension are important topics in physics. Students who want to flourish in physics need to be well known about the term surface energy to get deep knowledge about it to do well on their exams and it is very much useful in real life. The dimension, unit, and examples of surface energy are provided here to assist students in effectively understanding the respective topic. Continue to visit our website for additional physics help.
Overview:
Surface energy is the work performed on the outer surface of a material in which an atom is not bound to another atom in its immediate vicinity. Atoms of all substances must bond with other atoms. This is because most of the unchanging physical aspects of the matter are completely surrounded by bound atoms. However, as the material approaches the tip and reaches the surface, the bonds of the atoms break and there are no bonds on the outer surface of the material. This is called surface energy. A higher surface energy means that atoms have a stronger tendency to reconnect valence bonds.
Whenever a spring is stretched, some work is done to the spring and stored in the form of potential energy known as elastic potential energy. We can say that if the body were in an undeformed state, there would be no potential energy.
Similarly, when we talk about a free liquid surface, since we know that a free liquid surface is considered to be a stretched film, the surface will store some potential energy due to the stretched surface, which is only in the surface of the liquid. This is called surface energy or surface free energy.
Surface Free Energy:
Surface energy is the potential energy of a liquid molecule that helps the molecule stay on the surface of the liquid.
All molecules on the surface try to reach the bottom layer, so the surface energy decreases. Surface energy is the amount of work done to increase the surface area of a liquid.
Mathematically, the surface energy is the work performed per unit area of the liquid surface.
That is,
Surface energy = Work Done / Area = Joules /m²
The SI unit (International System of Units) of surface energy is Joules /m² or Newton /metre(N/m).
And the dimensional formula for surface energy is MT-2.
If the surface is very less, then the liquid surface will exert high surface energy.
For example, metals, oxides, and ceramics possess high surface energy.
In the same way, if the surface area is more, then the surface will exert low surface energy.
For example, Plastics, Rubbers, etc possess high surface energy.
The materials which possess low surface energy are classified as low surface energy materials.
Relationship Between Surface Energy and Surface Tension:
We have,
Surface Energy = Energy Area
= Joule m²
= Newton mm²
= Newton m
= Force Length
= Surface Tension
The surface tension of each and every material is different. Therefore, the surface energy of the materials will also be varying from one material to another. That is, the surface energy of liquid will be different from that of the surface energy of metals. As we know, the surface energy of water will be depending upon the angle of contact.
The surface energy of a few materials is:
| Material | Surface Energy mJ/m² |
| Glass | 83.4 |
| Water | 73 |
| Copper | 1650 |
| Polystyrene | 40.6 |
| Lead | 442 |
Also read: Surface Tension Physics Formula
Frequently Asked Question (FAQs):
Question 1: What is the Dimensional Formula of Surface Energy?
Answer: Surface energy has the dimensional formula MT-2.
Question 2: What is an example of surface energy?
Answer: Surface energy is easy to explain using bread as an example. Bread is considered a material both physically and chemically. The bulk or interior of material is filled with atoms bonded to each other. Other examples of materials that generate surface energy are metals and polyethylene. Metals have higher surface energy because the material is more brittle, so more surface energy is produced. They are counted in order of size. Likewise, polyethylene has lower surface energy.
Question 3: What are the main uses of surface energy?
Answer: Surface energy is the most commonly measured property in reverse GC. You can buy something that measures other properties such as heat absorption and surface area. Solubility parameters can be measured. It is based on the Fawkes principle and has been demonstrated in reverse gas chromatography, contact angle, and other surface energy methods. It is determined by a number of non-polar straight-chain alkane molecules. The interaction of these non-polar molecules then gives the non-polar or dispersed component of the surface energy.
Question 4: What is an important point to remember when writing about surface energy?
Answer: Surface energy is defined as the excess energy at the surface relative to the volume of the material. So, in mass we have all three closest neighbours in all three directions, filled with bonds and connected to other atoms, but we have all this free energy because of the lack of atoms on the surface compared to matter. to the main mass. This is because the atoms of the material are weakened without bonding, trying to generate energy to bind to the surface. So this work done by atoms is called surface energy.
