What is a pencil made from???
Where do they come from???
By, Mr. Howard Period 2
Cool Pencil History Factoids!
• Ancient Romans
called scribes used
to use rods of metal
to write on papyrus.
• First mass produced
pencils were in
Germany, in 1662.
Oldest Known WoodCased Pencil
MATERIALS FOUND IN A PENCIL
• A PENCIL is made from three main
ingredients:
– Synthetic Rubber. This is a
COMPOUND. It is made from
fossil fuels (hydrocarbons), so it
contains Carbon and Hydrogen.
– Incense Cedar Wood.
This is a MIXTURE. It has
“cellulose” fibers, formula
C6H10O5.
– Graphite (they don’t use lead
anymore; toxic!). Graphite is an
ELEMENT, formula C (pure
carbon)
Chemical and Physical Properties
Rubber Eraser
(HydroCarbon)
Density: 0.91 g/cm3
Melting Point: -183 C
Boiling Point: -164 C
Normal State: Gas
(Must be mixed with
• Incense Cedar
Wood (CelluloseC6H10O5)
Density: 0.38 g/cm3
Melting Point: None
Boiling Point: None
Normal State: Solid
other polymers to
Soluble? NO
make it into a solid).
Flammable? Yes!
Soluble? Not in water
Flammable? VERY!!
Graphite (pure
carbon)
Density: 2.09 g/cm3
Melting Point: 3500 deg C
Boiling Point: 3600 deg C
Normal State: SOLID
Soluble? Not in water.
Flammable? Generally no,
only at EXTREMELY high
temps!
Where does the “RUBBER” of a pencil
come from?
• Hydrocarbons are “fossil
fuels” (dead dinosaurs!),
so we get them from the
ground.
• Most comes from
Middle East and
domestic sources.
• Environmental
concerns- factory
pollution from
processing the oil, and
oil spills.
Where does the WOOD of a pencil
come from?
• Most cedar wood is
harvested in the Pacific
Northwest (our home!!).
• One concern is clearcutting forests destroys
habitat for other species
and contributes to
erosion which damages
salmon streams.
Where does the GRAPHITE of a pencil
come from?
• Graphite is mined around the
world in Italy, Finland, and the
US (New Jersey, Colorado,
Arizona).
• It is extracted from
open pit mines.
• Open pit mining destroys
large areas of land, and
creates toxic water and waste
products.
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