Hi there, everyone! It’s me, the Tin Mole from Oz. I’ve been stuck here for
many, many years waiting for someone to help me. You see I was on my way to Oz when it
began raining. I rusted, and have been here ever since. It’s a lonely life I
live…all alone with no one to talk to. I’m not a diatomic molecule, so exist by
myself in my free elemental state. But enough small talk—it looks like I’m going
to be here for a while. While we’re waiting for someone, I’ll tell you a little
about myself.
I am the infamous Tin Mole. Now, I’m sure you are wondering
what a mole is exactly. Let me explain: a mole is a fixed number, similar to a dozen,
which describes a number of particles as well as a quantity of mass. The fixed number is
called Avogadro’s number. It’s value is extremely large: it is 6.02 x 1023!
I know this all sounds very confusing, but here is an example. In one mole of tin, there
are 6.02 x 1023 atoms. In one mole of tin there are also 118.7g. One mole of
Tin (IV) oxide contains 6.02 x 1023 molecules, and 150.7g SnO2. A
mole is used as a conversion ratio in dimensional analysis too. Mole can be used in
converting to/from the atomic mass of an element, the formula mass of an ionic compound,
the molecular mass of a molecular compound, or atoms and molecules.
Now that you understand what a mole is, let me tell you a bit about the history of
myself, tin. Tin has been known about since ancient times. I was even mentioned in the Old
Testament! Since I am so old, people do not know when or by whom I was discovered. Metal
workers have used me since ancient times. They often found me too soft of a metal for most
purposes, so they mixed me with copper to create the alloy bronze.
Tin is the fiftieth element on the Periodic Table of Elements. . My chemical symbol,
Sn, comes from the Latin word for tin, which is "stannum." I have an atomic
number of 50, and an atomic weight of 118.7 grams. I am in Group 14, and Period 5 on the
Periodic Table. Tin is a silver-white metal, and has oxidation numbers +2 and +4.
Ordinary tin has nine stable isotopes and eighteen known unstable isotopes. I am
malleable, and somewhat ductile. My boiling point is 2, 270O
C, and my melting point is 231. 9O C. I have a density of
7. 30g/mL, and a specific heat of 2.3 x 10-1 J/g OC.
I resist distilled sea and soft tap water, but am attacked by strong acids, alkalis, and
acid salts.
I am mostly found in the form of SnO2, or Stannic oxide. The majority of the
world’s supply of tin comes from Malaya, Bolivia, Indonesia, Zaire, Thailand, and
Nigeria. The United States produces almost none of the tin; however, some has been found
in Alaska and California. Tin is obtained in an interesting way—by reducing the ore
with coal in a reverberatory furnace.
Tin is used in a variety of ways. I am often used to coat other metals to prevent
corrosion or other chemical action. Tin plating is commonly used over steel in cans for
preserving food. Window glass is made by floating molten glass on molten tin to produce a
flat surface. Tin salts sprayed onto glass are used to produce electrically conductive
coatings, which have been used for panel lighting and frost-free windshields. Some common
alloys of me are: soft solder, type metal, fusible metal, pewter, bronze, bell metal,
Babbitt metal, White metal, die casting alloy, and phosphor bronze. I am extremely useful
in the world!
Well, today looks like it may be my lucky day! Here comes a girl, little dog, and
funny-looking scarecrow down the path! Sorry to leave you so abruptly, but if I don’t
get their attention I may be stuck here many more years. Who knows when someone else will
come down this path! Hopefully this will be the one who can oil me so I can finally get to
the Emerald City…
