Why are Metals Good Conductors of Electricity?

Before we talk about why metals are good conductors of electricity, let us find out what is the difference between a good and a bad conductor of electricity. A good conductor of electricity is one such material that allows easy passage of electricity through it without much resistance. On the other hand, a bad conductor of electricity is the one that prevent free flow of electric current through it. In other, a good conductor has high conductance and low resistance and a bad conductor has low conductance and high resistance.

Why are Metals Good Conductors of Electricity and Heat?

We all know, that the smallest unit of all elements is atom. An atom is a neutral particle with a positively charged nucleus at the center and negatively charge electrons are moving in a number of orbits around the nucleus. The electrical conductivity of an element is determined by its atomic structure. There are several millions of atoms in a piece of metal. Each atom of a metallic element have two or three electrons in its outermost orbit which are also known as valence electrons. The atoms form metallic bond with each other to give a closely packed stable structure to the metal. During formation of these bonds, the valence electrons present in the outermost orbit are completely detached from their parent atom and can move freely in the space that lies within the lattice structure of the metal. When there is no electric field, then the electrons move around in a scattered manner in different directions. On application of an electric field, the electron starts flowing from one end to the other end of the metal. Thus the large number of free-flowing electrons are responsible for conducting electricity through the metal. They act as charge carriers and carry electricity through the structure of the metal.

Now let us talk about why are metals conductive to heat. Again, the answer is because there are plenty of free moving electrons in them. Heat get transmitted easily through metals by the means of free electrons. When heat is applied to the metal, then the free electrons near the source of heat gain a lot of energy and start moving rapidly. As the metal has a close packed structure, the energized free electron collide with other nearby electrons. This helps the vibration to pass on to the adjacent area in no time. Thus heat is transmitted through a metallic substance at a fast pace.

Which Metals are Good Conductors of Electricity?

Almost all existing metallic elements are conductor of electricity. Some metals have higher conductance than others. Those chemical elements that are considered as very good conductors of electricity are as follows:

• Copper
• Silver
• Aluminum
• Gold
• Nickel
• Chromium
• Iron
• Magnesium
• Mercury
• Titanium
• Molybdenum

Even though the conduction or transmission of electricity takes place through all metals in the same manner, their level of electrical conductivity is not the same. In other words, the ability to transmit electric current is different for every metal. Silver is considered as the best conductor of electricity and is followed by copper and then gold. When it comes to the use of metals for electrical applications, then copper is more widely used than silver. This is because silver is much more expensive as compared to copper. Therefore, low cost of copper makes it a more viable option for practical use in various electric and electrical equipment.