OH MY GOSH~! I accidentally stuck half centimeter of a pencil lead on my finger-tip! Is there any possibility that I will get into lead poisoning?
Ladies and gentlemen, do not panic as pencil lead is not really the lead, it is a non-toxic mixture which is made of graphite and clay now. It is known as lead because of the graphite marked like lead and last time the pencil is made of lead, so until now there is still some of the people thought pencil is made of lead. Well, as I said the pencil lead is now made of graphite and clay, not the actual lead.
Graphite is a giant covalent molecule which has many planes. The forces which hold between the planes are actually weak Van der Waals force. The planes may slip over each other and the C-C bonds are strong.
Friend of pencil – Eraser
Before the eraser being invented, the bread was used to erase the marked of pencil. Typical erasers are made from synthetic rubber. Eraser is make by which the tiny globes or spheres of rubber are bunched together.
How the erasers work?
When we made a mistake with pencil, we rub it with the eraser. But why the mark vanished after rubbing with eraser? It is because the eraser can breaks the bond between the graphite and the bond between the planes. Eraser also picks up the graphite particles when breaking the bond between the C-C particles of the planes.
Hence, leaves a clean white paper. There will be a residue or dust after rubbing, it is because of the tiny globes or spheres of rubber from the rubber which bunched together loose. So with these properties, we may rub off the mistake made by pencil with the help of eraser easily.
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