Metal are good conductors because they have large numbers of electrons
within their makeup that have energies that allow them to exist in the
conduction band. These are the so-called fee electrons that roam the
metallic crystal matrix. When we apply a voltage across a metal, the
free electrons are available to support the current flow.
Remember that current flow is a "shifting" of charges. If an
electron enters one end of a wire, it doesn't not travel the wire and
come out the other end. Rather, all the free electrons in the wire
"move over" one position, and an electron emerges from the other end.
With lots of free electrons, the metals are really good at this.//
Basically in metals there are free held loose electrons which increases their capability of conduction of energy either electricity or heat. Copper and Aluminum are the good conductors in metals. In scientific language they conduct energy because they have unfilled spaces in the valence energy band.
Basically there are some electrons in the outermost shell of the metals and these electrons when exposed to light or heat get excited and jump in the empty place of the energy band. In this way electrons keep on moving and transfer energy from one point to another. Although graphite is a form of carbon but in a certain direction it also conducts energy because of the arrangement of atoms.
Conductivity depends on the material of the conductor.... Also the cross-sectional area of the conductor matters...... The length as well because the greater the length the greater the resistance.... And yet another factor is temperature.. Higher temperature has a lower resistance as the molecules vibrate more and transfer energy faster..
Metals are substances which have one, two or three electrons in their valence shells. They are found naturally as ores, in their raw form, beneath the surface of the earth. They are mined and processed for purification and use. The process is called metallurgy and is specific for different metals, involving different steps. Minerals are widely used on account of their unique properties. They are known to be strong and ductile. They also have high melting points and allow thermal and electrical conductivity, which means the easy flow of heat and electricity. These properties are responsible for the growing industrial and domestic use of metals.
The atoms in metals are attached to one another via strong and delocalized bonds. These bonds are formed by a cloud of valence electrons that are shared between positive metal ions or cations in a crystal lattice or network. The unique arrangement is such that the valence electrons have considerable mobility and this is the property that enables the transfer of or conductivity of heat and electricity.
This property of metals makes them indispensable to the electronics industry. The ability of metals to be able to be drawn out into thin wires (ductility), together with the ability to conduct heat and electricity easily and without risk make metals ideal for industrial application.
Metals are basically a kind of elements. These elements are different because they readily lose electrons in order to form cations or positive ions. They also form metallic bonds between other metal atoms.
Metals are characterized as good conductors of electricity and heat. This is primarily because they have space in their valence energy band that is unfilled. When there is no electric field, the conduction electrons travel in all directions with high velocities. This happens at even the most coldest temperatures such as absolute zero. Thus when an electric field is applied, an imbalance develops and the mobile electrons flow from the outer band.
The resistance for conduction comes in metals when scattering of electrons occurs due to defects in the lattice.
To understand this question you must first consider the very basic properties of metals.
Metals have different properties to both ionic and covalent compounds. As we have all heard that in metals positively charged ions are embedded in a sea of electrons. This is true as in a metallic lattice; the atoms lose their outer-shell electrons to become the "positive ions". While the electrons which are removed are free to move around the ions. They however revolve around the positive ions due to the attraction of the proton from the nuclei. Here we get to know why all metals form positive ions.
Now, coming to their property of conducting heat and electricity As above mentioned there are free electrons which roam around the positive ions conduction of electricity may take place in any direction (in insulators electricity kind of becomes trapped as the electrons are not free to move). Conduction of heat takes place as the heat occurs by vibration of the positive ions as well as via the mobile (free) electrons. As in any other type of bonding there is not much independence given to positive ions or electrons metals have the upper hand in conducting heat and electricity compared to other types of compounds, because of the metallic bonding.
Hope that answers your question.
The conductivity of a material is determined by the energy needed to excite electrons in the outer most shells of its atoms or molecules. Once the electrons are excited, they can move around the material. The molecules in metals are most easily moved.
Because they have a large number of poorly bound electrons. These electrons form an electron cloud when large numbers of metalic atoms are together.
If you add some electrons to one side of a bunch of metalic atoms other electrons will pop out on the other side. If this bunch of metalic atoms are in the form of a wire, well you have a wire conducting electricity.
The diagram would be like this:
- - - - - - - - - -
- - (+)(+)(+)(+)(+)(+)(+)- -
- - - - - - - - - -
(+) positive ions
- delocalized electrons