yes it is waterproof
No. Also, "pencil lead" is not lead; it is almost always graphite (made of carbon)
yes yes it is
the point, I think, is either the amount of different substances in the graphite/lead, or even the type of eraser...
There are a lot of advantages to pencils. They don't dry up like pens, for one. They're also eraseable and allow for shading. Thinking more abstractly, they are a direct reflection of how much work you've done with them—the shorter the pencil (or the inner lead in a mechanical pencil), the more work you've done. There are disadvantages, too. They are in constant need of maintenence (sharpeners, extra pieces of lead, etc.) and tend to smudge as you run your hands across their markings.
what is a qualitative example of a pencil
Yes they are waterproof.
A typical lead pencil does not actually contain lead. The "lead" in a pencil is made of graphite, which is a crystalline form of carbon. Therefore, there is 0% lead in a lead pencil.
There is no lead in pencil - Pencil is made from graphite
Pencil lead is a compound
If your asking if the pencil has Lead, then the answer is that most pencils do NOT have lead in them anymore.
Pencil lead isn't really lead, it is graphite, a form of carbon. Pencil lead doesn't have any lead in it whatsoever.
we get lead of pencil from the mixture of clay and graphite
Pencil lead is a conductor.
A 9mm pencil lead is thicker than a 7mm pencil lead.
Pencil lead is made of graphite and clay. Newer recipes for pencil lead use waxy polymers to bind the graphite to produce a lead that does not snap when the pencil is flexed.
lead pen because a lead pencil is a regular pencil.
Because there is no lead in them any more.