Chemistry Project On Coin Analysisthechemistryguru.com/wp-content/uploads/2017/12/... · Chemistry...
Transcript of Chemistry Project On Coin Analysisthechemistryguru.com/wp-content/uploads/2017/12/... · Chemistry...
1 www.thechemistryguru.com
Chemistry
Project
On
Coin
Analysis
2 www.thechemistryguru.com
AIM
Qualitative
Analysis
Of
Different
Coins
3 www.thechemistryguru.com
CERTIFICATE
This is hereby to certify that, the original
and genuine investigation work has been
carried out to investigate about the subject
matter and the related data collection and
investigation has been completed solely,
sincerely and satisfactorily regarding her
project titled “Qualitative Analysis of
Coins”.
Teacher’s Signature
4 www.thechemistryguru.com
ACKNOWLEDGEMENT
It would be my utmost pleasure to express
my sincere thanks to My Chemistry Teacher
Mrs./Mr.__________, in providing a helping
hand in this project. Her valuable guidance,
support and supervision all through this
project titled “Qualitative Analysis of
Coins”, is responsible for attaining its
present form.
5 www.thechemistryguru.com
PURPOSE
I was interested in finding out the contents
of the coins we use in everyday life money
transactions. Humans have been using coins
since their invention in 700 B.C. for trading
of goods and services.
Another fact which inspired me to do this
project is that I am in touch with qualitative
analysis whose knowledge with other factors
helped me to do so.
6 www.thechemistryguru.com
CONTENTS
Introduction
Theory
Apparatus
Chemicals Required
20 Paise Coin (India)
1 Cent Coin (U.S.A)
2 Rupee Coin (India)
1 Rupee Coin (India)
Result
Conclusion
7 www.thechemistryguru.com
INTRODUCTION
An alloy is a mixture or metallic solid solution
composed of two or more elements. Complete solid
solution alloys give single solid phase-microstructure.
Alloys usually have different properties from those of
the component elements.
Alloying a metal is done by combining it with one or
more other metals or non-metals that often enhance its
properties.Alloys are used in ornaments, bells, statues,
buildings, and even coins.
Coins-A Historical Approach
The history of coins extends from ancient times to the
present, and is related to economic history, the history
of minting technologies, and the history of coin
collecting. Coins are still widely used for monetary and
other purposes.
Since the time they were invented in 700 B.C., coins
have been the most universal embodiment of money.
8 www.thechemistryguru.com
The first coins were made of electrum, a naturally
occurring pale yellow mixture of gold and silver that
was further alloyed with silver and copper.
Some of the earliest coins were beaten at the edges to
imitate the shape of a cow, in indication of their value.
Most coins are circular but some were rectangular. Also
a lot of coins, especially in China had a hole through
the center so they could be tied on to a string.Some of
the earliest coins to be made purely from silver and
gold were the silver Dirham and gold Dinar.
Coins were first made of scraps of metal. Ancient coins
were produced through a process of hitting a hammer
positioned over an anvil.The Chinese produced
primarily cast coinage, and this spread to South-East
Asia and Japan.
The type of mintage method (being hammered, milled
or cast) does limit the materials which can be used for
the coin. For example antimony coins, (which are very
rare) are nearly always cast examples, because of the
brittle nature of the metal, and thus it would break if
9 www.thechemistryguru.com
deformed, which is a key part of the milling or
hammering process.
Coins today are of great value and are used in our day-
to-day lives.
10 www.thechemistryguru.com
THEORY
A coin is a piece of hard material that is standardized
in weight, is produced in large quantities in order to
facilitate trade, and primarily can be used as a legal
tender token for commerce in the designated country,
region, or territory.
Coins are usually metal or a metallic material and
sometimes made of synthetic materials, usually in the
shape of a disc, and most often issued by a government.
Coins are used as a form of money in transactions of
various kinds, from the everyday circulation coins to
the storage of large numbers of bullion coins. In the
present day, coins and banknotes make up currency,
the cash forms of all modern money systems.
An alloy is a homogeneous mixture of two or more
metals or a metal and non-metal.
They are generally harder than their components with
reduced malleability and ductility. Alloys are prepared
11 www.thechemistryguru.com
to enhance certain characteristics of the constituent
metals, as per requirement.
The coinage metals comprise, at minimum, those
metallic chemical elements which have historically
been used as components in alloys used to mint coins.
Coins that are intended for circulation have some
special requirements based on the conditions they will
encounter. For example, a coin may be in circulation for
up to 30 years, and so must have excellent wear
resistance and anti-corrosion properties. Achieving this
goal necessitates the use of base metal alloys. Some
metals like manganese have occasionally been used in
coins, but suffer from making the coins too hard to take
an impression well.
A common base metal alloy for everyday coinage is
Cupro-Nickel (also cupronickel), with varying
proportions of copper and nickel, most commonly 75%
Cu 25% Ni. Cupronickel has a silver color, is hard
wearing and has excellent striking properties, essential
for the design of the coin to be pressed accurately and
quickly during manufacture.
12 www.thechemistryguru.com
APPARATUS
Test Tubes
Test Tube Holder
Test Tube Stand
Beaker
Burner
Tripod Stand
pH Paper
Wire Gauge
Water Bath
Filter Paper
13 www.thechemistryguru.com
CHEMICALS REQUIRED
Hydrochloric Acid (HCl)
Sodium Hydroxide
Hydrogen Sulphide Gas
Nitric Acid (HNO3)
Ammonium Acetate
Potassium Iodide
Potassium Chromate
Potassium Ferrocyanide
Ammonium Hydroxide
Ammonium Chloride
Potassium Sulphocyanide
Potassium Nitrite
Ammonium Thiocyanide
Dimethyl Glyoxime
Bromine Water
Ammonium Carbonate
Ammonium Phosphate
14 www.thechemistryguru.com
Twenty Paise Coin (India)-Made in 2003
Experiment Observation Inference
Zero Group:
Add concentrated
solution of
No white fumes
observed. Ammonia (NH4
+) is absent.
sodium
hydroxide(NaOH) to it.
Group I:
Add dilute solution of
No white precipitate
formed. Pb2+, Ag2+ and Hg2
2+ are absent.
hydrochloric acid to the
original
solution.
Group II:
Add dilute solution of
HCl to
No black or yellow
precipitate formed.
Pb2+, Cu2+,As3+ are
absent.
the original solution
and pass
H2S gas through it.
Group III:
Add NH4Cl and
NH4OH(in
A white precipitate is
obtained. Al3+ may be present.
excess) to the original
solution.
15 www.thechemistryguru.com
Confirmatory For
Cl3+:
Lake Test:
Dissolve the white
precipitate
Blue precipitate is
observed
obtained int dilute HCl.
Add to
floating in the
colourless Al3+ is present.
it two drops of blue
litmus solution.
solution. To this, add
NH4OH
drop wise till blue
colour
develops.
Group IV:
Use the same solution
as used No precipitate formed.
Co2+,Ni2+,Mn2+ and Zn2+
are
in Group III tests and
pass H2S absent.
gas through it.
Group V:
To the original solution,
add
No white precipitate
formed.
Ba2+, Ca2+ and Sr2+ are
absent.
NH4Cl, NH4OH and
(NH4)2CO3.
Group VI:
To the original solution,
add
A white precipitate is
obtained. Mg2+ may be present.
NH4Cl, NH4OH (in
excess) and
(NH4)2HPO4.
16 www.thechemistryguru.com
RESULT
Twenty Paise Coin of India contains
Aluminium(Al3+)and Magnesium(Mg2+).
17 www.thechemistryguru.com
One Cent Coin (U.S.A)-Made in 1987
Experiment Observation Inference
Zero Group:
Add concentrated
solution of
No white fumes
observed. Ammonia (NH4
+) is absent.
sodium
hydroxide(NaOH) to
it.
Group I:
Add dilute solution of
No white precipitate
formed. Pb2+, Ag2+ and Hg2
2+ are absent.
hydrochloric acid to the
original solution.
Group II:
Add dilute solution of
HCl to
A black precipitate
obtained. Cu2+ may be present.
the original solution
and pass
H2S gas through it.
Confirmatory for
Cu2+:
Heat the black
precipitate with
1-2 ml of 50%
HNO3.The
Blue coloured solution
obtained. Cu2+ may be present.
precipitate dissolves
and add
dilute H2SO4 and
alcohol.
18 www.thechemistryguru.com
When there is no white
precipitate,add NH4OH
in excess.
Potassium
ferrocyanide test:
To one part of the blue
solution
A chocolate brown
precipitate is Cu2+ is present.
add acetic acid and
potassium obtained.
ferrocyanide solution.
Potassium Iodide
test:
A white precipitate is
formed in Cu2+ is present.
To another part add
acetic acid
the brown coloured
solution.
and potassium iodide
solution.
Group III:
Add NH4Cl and
NH4OH(in
A white precipitate is
obtained.
Al3+,Cr3+,Fe3+,Fe2+ are
absent.
excess) to the original
solution.
Group IV:
Use the same solution
as used
A dull white precipitate
is obtained. Zn2+ may be present.
in Group III tests and
pass H2S
gas through it.
19 www.thechemistryguru.com
Confirmatory for Zn2+:
Sodium hydroxide
test:
To one part of the
original
A white precipitate is
obtained. Zn2+ is present.
solution add sodium
hydroxide
Add more NaOH to
dissolve the
solution drop-wise. precipitate.
Potassium
ferrocyanide test:
To another part, add
potassium A white or bluish white Zn2+ is present.
ferrocyanide solution. precipitate.
RESULT
Twenty Paise Coin of India contains Zinc (Zn2+) and Copper
(Cu2+).
20 www.thechemistryguru.com
Two Rupees Coin (India)-Made in
2003
Experiment Observation Inference
Zero Group:
Add concentrated
solution of
No white fumes
observed. Ammonia(NH4
+) is absent.
sodium
hydroxide(NaOH) to it.
Group I:
Add dilute solution of
No white precipitate
formed. Pb2+, Ag2+ and Hg2
2+ are absent.
hydrochloric acid to the
original solution.
Group II:
Add dilute solution of
HCl to
A black precipitate
obtained. Cu2+ may be present.
the original solution
and pass
H2S gas through it.
Confirmatory for
Cu2+:
Heat the black
precipitate with
1-2 ml of 50%
HNO3.The
Blue coloured solution Cu2+ may be present.
precipitate dissolves
and add
dilute H2SO4 and
alcohol.
obtained.
21 www.thechemistryguru.com
When there is no white
precipitate,add NH4OH
in
excess.
Potassium
ferrocyanide test:
To one part of the blue
solution
A chocolate brown
precipitate Cu2+ is present.
add acetic acid and
potassium is obtained.
ferrocyanide solution.
Potassium Iodide
test:
A white precipitate is
formed in Cu2+ is present.
To another part add
acetic acid
the brown coloured
solution.
and potassium iodide
solution.
Group III:
Add NH4Cl and
NH4OH(in
A white precipitate is
obtained.
Al3+, Cr3+, Fe3+, Fe2+ are
absent.
excess) to the original
solution.
Group IV:
Use the same solution
as used
A black precipitate is
obtained.
Ni2+ may be present.(If
the
in Group III tests and
pass H2S
original solution is
green).
gas through it.
22 www.thechemistryguru.com
Confirmatory for Ni2+:
Dimethyl glyoxime
test:
To one part of the
original
A bright rose red
precipitate is Ni2+ is present.
solution add
ammonium obtained.
hydroxide solution and
few
drops of dimethyl
glyoxime.
Sodium hydroxide -
bromine
water test:
A black precipitate is
obtained. Ni2+ is present.
To another part add
sodium
hydroxide (in excess)
and
bromine water and
boil.
RESULT
Two Rupee Coin of India contains Copper (Cu2+) and Nickel (Ni2+).
23 www.thechemistryguru.com
One Rupee Coin (India)-Made in 2010
Experiment Observation Inference
Zero Group:
Add concentrated
solution of
No white fumes
observed. Ammonia(NH4
+) is absent.
sodium
hydroxide(NaOH) to it.
Group I:
Add dilute solution of
No white precipitate
formed. Pb2+,Ag2+ and Hg2
2+ are absent.
hydrochloric acid to the
original solution.
Group II:
Pb2+, Cu2+, As3+ are
absent.
Add dilute solution of
HCl to
No black or yellow
precipitate
the original solution
and pass formed.
H2S gas through it.
Group III:
Add NH4Cl and
NH4OH(in
A reddish brown
precipitate is Fe3+ may be present.
excess) to the original
solution. obtained.
Confirmatory for
Fe3+:
Dissolve the reddish
brown
precipitate in dilute
24 www.thechemistryguru.com
HCl, and
divide the solution into
two
parts.
Potassium
ferrocyanide test:
To one part of the above
Prussian Blue
colouration is Fe3+ is present.
solution add potassium obtained.
ferrocyanide solution.
Potassium
sulphocyanide test:
To the second part, add
a little Blood red colouration is Fe3+ is present.
potassium
sulphocyanide obtained.
solution.
RESULT
Two Rupee Coin of India contains Iron (Fe3+).
25 www.thechemistryguru.com
RESULT
Amount Country Year Ions present
Twenty Paise
Coin India 1938 Al3+
and Mg2+
ions
One Cent Coin U.S.A 1987
Cu2
+
and Zn2+
ions
Two Rupee Coin India 2003 Cu2+ and Ni2+
ions
One Rupee coin India 2010
Fe3
+ ion
26 www.thechemistryguru.com
BIBLIOGRAPHY
LABORATORY MANUAL OF CHEMISTRY
WEBSITES —Www.thechemistryguru.com