General Knowledge - General Science - Discussion

Discussion Forum : General Science - Elements and Metals (Q.No. 4)
4.
Which of the following is used in pencils?
Graphite
Silicon
Charcoal
Phosphorous
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
121 comments Page 1 of 13.

Noor Zahra said:   2 years ago
As graphite is an allotrope of Carbon, it shows a layering structure. Pencil cast an impression on paper because graphite is made up of carbon atoms and paper is made up of cellulose. Cellulose is an organic polysaccharide compound as we know all organic compounds are made up of carbon atoms. So both paper and graphite have carbon atoms in common so the carbon atom of graphite makes a covalent bond with the carbon atom of paper so the mark is cast. As graphite is mettloid its conductivity decreases with increase in temperature. It's color is black because when carbon black is heated to very high temperature for a long time then graphite is made. So, graphite is made from carbon black so the color of graphite is also black.
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Kamalesh said:   1 decade ago
The graphite is an allotropic form of carbon that consists of atoms of carbon that possesses a kind of hybridization in a way that three strong bonds are forming a equilateral triangle in the same plane and a weaker bond perpendicular to that plane.

This allows that carbon arranged in parallel "sheets" that slide one each other giving the graphite a high lubricant performance.

That is the reason that is used in lead pencils: each graphite sheet slides on the paper surface when we write on it, leaving carbon atoms adhered on it. We saw the result as writing characters.

Ashish said:   1 decade ago
Aside from being the material in your lead pencils, graphite is of tremendous value as an industrial material. It is used to make the brushes for electric motors and generators, and it has wide use as an electrode in a number of applications, primarily batteries.

Graphite has been, is, and will continue to be critically important to maintaining and advancing modern civilization. And this because it is in things we use every day, and because it is used in industrial processes that provide the foundation we build our society on.

Lily said:   9 years ago
Graphite is another giant covalent structure made of carbon atoms. In graphite, each carbon atom is joined to three others, forming layers:.

Diagram showing graphite structure.

The bonds between the layers are much weaker than covalent bonds. This enables the layers to slide over each other, making graphite soft. Graphite can also conduct electricity, between the layers of carbon atoms.

Graphite is used as pencil 'lead'. As the pencil moves across the paper, layers of graphite rub off.

Abdul_Muhsin said:   10 years ago
As pencil is slippery in touch and the graphite is also slippery in touch. Also pencil is black in color as graphite is. People believe that mankind in stone age used a graphite stone to write on mud so scientist even tried to do same so pencils were created.

Graphite is very soft to easy sharp and very easy write on paper and its smoothly removable. Graphite is a non metal.

It is a good conductor. If a pencil point touch the electric current. It we give a spark & chocking smell.

Sammi said:   8 years ago
Yes, graphite is the right answer because it allows all the carbon particles to arrange themselves in such a way that they form a parallel line to each other and allow the graphite to work smoothly like a lubricate. And also before they were using lead which was very poisonous and dangerous then they started using this graphite instead of the lead in the pencil "which is smooth, dark or black in colour.

Chith said:   1 decade ago
Graphite slides easily on any surface and has a loose carbon structure, so as for it being used in pencils, pencil lead has to be smooth and slide across the paper to write properly. Also, graphite is naturally a very dark grey, almost black colour. The same as pencil lead. Note: Just because we call pencil lead 'lead', it does not literally mean that it is made of lead; that's impossible.

Brianna said:   9 years ago
Well, technically, a pencil has the lead and it uses something to compress it to write the information needed. BTW's, in history, Egypt used a stylus to write. But, as my inference, I say it came from there to us. In some way shape and form they let us use their technique and we, the people, took it from there.

Tin said:   1 decade ago
Of couse graphite is used in making pencil leads but you know that graphite is a soft non metal and gets powdered easily in hand. So in order to make it hard its mixed with a substance. I don't exactly know the substance's name. If any one knows it please post it here as graphite is lustrous so to be used!

V.s.shabarish said:   1 decade ago
As we all know carbon is a black element and the graphite is the softest allotropes of carbon. If you try. To break a pencil you will find the middle black part (graphite).

Easily breaks it makes impression on light surface it imparts carbon to the surface of paper therefore graphite is used in pencil.


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