Uploaded by Sreemoyee Chakraborty

New York Most Famous Icon changed over time

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New York's most famous landmark is turned
green by the city's pollution
New York's iconic, blue-green statue of liberty wasn't always green.
When the statue was gifted to the US from France in 1885, she was actually a shiny copper color.
A new video reveals the chemical reactions involving oxygen and even air pollution that led to her
color change from copper to liberty green.
Pictured is the statue of liberty in 1900 during its color transition to the blue-green color it is today. The
statue's color change was as a result of oxidation reactions between copper and the air, a new video has
revealed
The statue of liberty was a gift from France to the US as a way of commemorating the US's fight for
independence, as well as their own aspiration for democracy.
A video, published by the American Chemical Society, explains that the 305-foot (93 meter) statue
was built over nine years in sections of copper skin on top of an iron
According to the National Park Service, the statue is made of thirty tons of copper - enough to make
435 million pennies.
'In her first few decades in the Big Apple, the state slowly turned from that shiny copper color to a
dull brown and the, finally, to the blue-green, or as they'd say back in France, 'verdigris' we see
today,' said the video's narrator.
When it changed color, some officials suggested restoring her back to her original color, but after the
public protested against this decision, she was left the way she is.
In the case of the statue of liberty, her color change was bound to happen due to oxygen in the
atmosphere that is 'hungry' for electrons.
Oxidation reactions happen when an atom loses an electron to another atom. In the case of the statue
of liberty, her color change was bound to happen due to oxygen in the atmosphere that is 'hungry' for
electrons. On top of this, elements of New York City's polluted air added to the color change too.
On top of this, elements of New York City's polluted air added to the color change too.
The statue of liberty was built over nine years in sections of copper skin on top of an iron
skeleton. According to the National Park Service, the statue is made of thirty tons of copper - enough to
make 435 million pennies
THE CHEMISTRY OF THE STATUE'S COLOR CHANGE
The first chemical reaction of the color change involved copper giving up electrons to electronhungry oxygen in the atmosphere.
This led to a mineral called culprite - which is pinkish red.
The feet of the statue of liberty (pictured) arrived on Liberty Island 1885. The statue was a gift from the
people of France to the United States, It represents Libertas, the Roman goddess of freedom
Then, culprite loses even more electrons to oxygen, forming a new mineral called tenorite, which is blackish in
color.
When sulfur dioxide in the atmosphere reacts with water, it produces sulfuric acid.
Tenorite reacts with sulfuric acid in the atmosphere and water to form brochantite, a blue-green mineral.
New York City pollution put even more sulfuric acid into the atmosphere, which converted brochantite into green
antlerite in some places on the statue.
And because of sea spray from Ellis Island, sulfate in the brochantite got swapped for chloride, making olivegreen atacamite.
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The statue's color change was as a result of oxidation reactions between copper and the air. But it was more
than one reaction - the color change is due to about 30 years worth of different reactions leading to a
mixture of greenish minerals
Sulfur comes from natural processes such as volcanic eruptions, but also from man-made emissions
from boats, cars, airplanes and factories.
When sulfur dioxide in the atmosphere reacts with water, it produces sulfuric acid.
The statue's color change was as a result of oxidation reactions between copper and the air.
+Tenorite reacts with sulfuric acid in the atmosphere and water to form brochantite, a blue-green mineral
The first chemical reaction of the color change involved copper in the state giving up electrons to electron-hungry
oxygen in the atmosphere.
This led to a mineral called culprite - which is pinkish red.
Then, culprite loses even more electrons to oxygen, forming a new mineral called tenorite, which is blackish in
color.
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