Why Diamond is a Poor Conductor & Graphite a Good Conductor

In summary, diamond is a poor conductor of an electric current because its molecules are tightly packed with no free electrons, making it a good insulator. On the other hand, graphite is a good conductor due to its flat structure and delocalized pi bonds, which allow for the flow of electricity through free electrons. The fundamental difference between the two substances lies in the arrangement of their carbon atoms, with diamond having tetrahedral molecules and graphite having flat groupings. By looking at the number of covalent bonds and the presence of free electrons, we can deduce the electrical conductivity of each substance.
  • #1
arabianchick
2
0
Why is diamond a poor conductor of an electric current and graphite a good conductor?

all i can come up with is that diamond is a good insulator and that the fundamental difference between graphite and diamond being that graphite molecules are flat groupings of carbon atoms while diamond molecules are tetrahedral (pyramid-shaped) groupings of carbon atoms.

can someone tell me if this is anywhere close? and help me on a bit..
 
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  • #2
look carefully at the structure of both diamond and graphite. find out how many covalent bonds are there for each carbon atom in both diamond and graphite.

what can you deduce?
 
  • #3
hint: delocalized pi bonds
 
  • #4
arabianchick said:
Why is diamond a poor conductor of an electric current and graphite a good conductor?

all i can come up with is that diamond is a good insulator and that the fundamental difference between graphite and diamond being that graphite molecules are flat groupings of carbon atoms while diamond molecules are tetrahedral (pyramid-shaped) groupings of carbon atoms.

can someone tell me if this is anywhere close? and help me on a bit..

Graphite and diamond are both made from carbon, which has 4 electrons in it's outer shell. Diamond has four bonds, meaning there are no free electrons. Graphite has three bonds giving it a free electron which alows the current of electricity to flow. Hope this helps.
 
  • #5


Yes, you are on the right track! The difference in the molecular structure of diamond and graphite is the main reason for their difference in conductivity. Diamond is made up of a three-dimensional lattice structure of carbon atoms, while graphite has a layered structure with flat sheets of carbon atoms stacked on top of each other. This difference in structure affects the movement of electrons, which is essential for electrical conductivity.

In diamond, the strong covalent bonds between carbon atoms make it difficult for electrons to move freely, making it a poor conductor of electricity. On the other hand, in graphite, the electrons are only weakly bonded to the carbon atoms within each layer, allowing them to move more freely between the layers. This makes graphite a good conductor of electricity.

Moreover, the presence of delocalized electrons in graphite also contributes to its high conductivity. These delocalized electrons are not tied to a specific atom and can move freely throughout the material, allowing for the easy flow of electricity.

In summary, the difference in molecular structure and the presence of delocalized electrons are the main reasons why diamond is a poor conductor of electricity, while graphite is a good conductor. This difference in conductivity is also why diamond is used as an insulator in electronic devices, while graphite is used in electrical components such as batteries and electrodes.
 

1. Why is diamond a poor conductor?

Diamond is a poor conductor because it is composed of tightly bonded carbon atoms arranged in a lattice structure. This structure does not allow for the free movement of electrons, which is necessary for a material to conduct electricity.

2. How is graphite able to conduct electricity?

Graphite is able to conduct electricity because it has a unique layered structure in which the carbon atoms are arranged in flat sheets. These sheets have delocalized electrons that are free to move and carry an electric current.

3. Is there any other difference between diamond and graphite besides their conductivity?

Yes, there are several differences between diamond and graphite. Diamond is the hardest known substance, while graphite is relatively soft. Diamond also has a higher melting point and is transparent, while graphite is opaque.

4. Can graphite be used as a conductor in electronics?

Yes, graphite can be used as a conductor in certain electronics. It is commonly used in pencil leads, as well as in batteries, electrodes, and as a lubricant. However, it is not commonly used in electronic circuits due to its lower conductivity compared to metals.

5. Why is diamond still used in electronics if it is a poor conductor?

Diamond is still used in electronics because it has excellent thermal conductivity and can withstand high temperatures and corrosive environments. It is often used as a heat sink in electronic devices, helping to dissipate heat and prevent overheating. Diamond also has low electrical resistance, making it useful in certain electronic applications such as high-frequency devices.

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