HEAVIEST...
Naturally occurring element
In 1971, US scientist Darleane Hoffman
published her discovery of small amounts
of plutonium-244 in Precambrian phosphate
deposits found in California, USA. Plutonium
has an atomic number of 94.Alkali metal to occur
in significant quantities
Occupying group 1, or the left-most column of
the periodic table, alkali metals are soft and
highly reactive, with low density. Although
caesium’s atomic number of 55 is lower than
that of francium (87), francium is only visible
in microscopic amounts in the Earth’s crust
and is invisible to the naked eye.Lanthanide metal
The lanthanide metals consist of the 15 elements
with atomic numbers 57 to 71 and are sometimes
known as the “rare earth elements”, along
with yttrium and scandium. Lutetium’s atomic
number of 71 makes it the heaviest of the group.Transition metal
All elements in groups 3–12 of the periodic table
(with the exception of lutetium and lawrencium)
are known as transition metals. Less reactive
than alkali metals, transition metals are good
conductors of heat and electricity and include
gold, copper and iron. With an atomic number
of 112, copernicium (Cn) is the heaviest of
these metals. First created in 1996, it is
a man-made element that does not
occur in nature.Element to produce a net release
of energy via nuclear fusion
Elements are created in the cores
of stars by a process called stellar
nucleosynthesis, in which the
protons and neutrons of lighter
elements are bonded together to form
heavier ones. Iron (atomic number 26) is the
heaviest element that can be created without
requiring additional energy. Stars producing
elements heavier than iron suffer a dramatic
drop in energy output, leading to collapse and
eventual supernova.Heavy Metal
EARTH
ELEMENTARY
SCHOOL
Every element on the
periodic table has its
own atomic number,
atomic weight and
chemical symbol.
Lead, for example,
has an atomic
number of 82, which
means there are
82 protons in every
atom. Its atomic
weight (or relative
atomic mass) is 207.2,
which is the ratio of
the average mass
of an atom of lead
compared to 1/12th
of the mass of an
atom of a carbon-12
isotope. Lead’s
chemical symbol is
Pb. It derives from
the Latin word
plumbum, which
means “liquid silver”.On Venus, it “snows” lead
and bismuth sulphides,
so the mountains are
capped with metalMore than half of the
world’s output of lead is
used to make car batteriesAn average 70-kg (154-lb)
human body comprises about
0.01% heavy metals (7 g, the
weight of two dried peas)Tooth cavities are filled
with “dental amalgam” –
a liquid alloy of mercury
and other metals. The
technique dates to 658 ce.Toxic arsenic trioxide
was mixed with chalk and
vinegar in Victorian times
to make face cream!The element cobalt (Co) was
named after “kobalt”, the
German word for goblinCigarettes often contain
the heavy metals
cadmium, lead, arsenic
and nickelEllis Hughes,^
a settler living in
Oregon,^ moved
the^
Willamette^ meteoriteto^
his^ own^ land^
in 1903,^ with^
the help of his son. It took
them^ 90 days^
to shift^
the vast stone just
1,200 m^ (3,940 ft)!MOST ABUNDANT METAL IN THE UNIVERSE
Iron (Fe) accounts for approximately 0.11% of all matter in the
universe. The sixth most common element overall, it makes
up around 0.1% of the Sun and 0.006% of a human being. It also
accounts for around 22% of meteorite material found on Earth- such as the famous WiIlamette Meteorite (left), a giant chunk of
iron-nickel space debris weighing 14.15 tonnes (31,195 lb) that was
discovered in the US state of Oregon.
Longest half-life by alpha decay
Half-life is the measure of how long it takes an
unstable element to decay. A half-life of one
day means that it would take that time for half
the atomic nuclei in a sample to decay into a
more stable element. In 2003, French scientists
discovered that bismuth-209, previously believed
to be radioactively stable, in fact gradually decays
with a half-life of around 20 billion billion years –
more than a billion times the age of the universe.First artificially produced element
Technetium (Tc) was discovered in 1937 by
Carlo Perrier and Emilio Segrè (both ITA)
at the University of Palermo in Sicily, Italy.
They isolated the element from a sample of
molybdenum (Mo), which had been exposed to
high levels of radiation in a particle accelerator
known as a cyclotron. Its most stable isotope,
technetium-98, has a half-life of around
4.2 million years, meaning that any significant
mineral deposits in the Earth’s crust have long
since radioactively decayed into ruthenium-98.Largest cluster of francium
atoms made in a laboratory
In Dec 2002, scientists at the State University of
New York, USA, managed to create francium (Fr)
atoms using a heavy ion nuclear fusion reactor,
collecting more than 300,000 together in a
magneto-optical trap. Francium’s most stable
isotope has a half-life of just 22 min, making
it the most unstable naturally occurring
element. It has no practical uses.Largest civil stockpile of plutonium
As of 2016, the UK held around 126 tonnes
(277,782 lb) of plutonium (Pu), 23 tonnes
(50,706 lb) of which is owned by other nations.
A by-product of uranium used in nuclear
reactors, the plutonium is stored at the
Sellafield nuclear site in Cumbria. It exists
in powdered form and is kept
in steel and aluminium
containers.As of 1700, only seven of the 84 metal elements on the periodic table were identified.
These “Metals of Antiquity” were gold, copper, silver, lead, tin, iron and mercury.Q: Which element makes up
most of the human body?
A: Oxygen. It accounts for around
65% of all the elements in us.