Chemistry Project On Coin Analysisthechemistryguru.com/wp-content/uploads/2017/12/... · Chemistry Project On Coin Analysis . 2 ... project titled “Qualitative Analysis of Coins”.

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Chemistry

Project

On

Coin

Analysis


AIM

Qualitative

Analysis

Of

Different

Coins


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


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.


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.


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


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.


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


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.


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


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.


APPARATUS

Test Tubes

Test Tube Holder

Test Tube Stand

Beaker

Burner

Tripod Stand

pH Paper

Wire Gauge

Water Bath

Filter Paper


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


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:


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.


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


formed.

Ba2+, Ca2+ and Sr2+ are

absent.

NH4Cl, NH4OH and

(NH4)2CO3.

Group VI:

To the original solution,

add


obtained. Mg2+ may be present.

NH4Cl, NH4OH (in

excess) and

(NH4)2HPO4.


RESULT

Twenty Paise Coin of India contains

Aluminium(Al3+)and Magnesium(Mg2+).


One Cent Coin (U.S.A)-Made in 1987


Zero Group:

Add concentrated

solution of

No white fumes

observed. Ammonia (NH4

+) is absent.

sodium

hydroxide(NaOH) to

it.

Group I:




2+ are absent.


original solution.

Group II:


HCl to

A black precipitate

obtained. Cu2+ may be present.


and pass

H2S gas through it.

Confirmatory for

Cu2+:

Heat the black

precipitate with

1-2 ml of 50%

HNO3.The

Blue coloured solution


precipitate dissolves

and add

dilute H2SO4 and

alcohol.


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:


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


obtained.

Al3+,Cr3+,Fe3+,Fe2+ are

absent.


solution.

Group IV:


as used

A dull white precipitate

is obtained. Zn2+ may be present.


pass H2S

gas through it.


Confirmatory for Zn2+:

Sodium hydroxide

test:

To one part of the

original


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+).


Two Rupees Coin (India)-Made in

2003


Zero Group:

Add concentrated

solution of

No white fumes

observed. Ammonia(NH4

+) is absent.

sodium


Group I:




2+ are absent.


original solution.

Group II:


HCl to

A black precipitate



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.


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.


Potassium Iodide

test:


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


obtained.

Al3+, Cr3+, Fe3+, Fe2+ are

absent.


solution.

Group IV:


as used

A black precipitate is

obtained.

Ni2+ may be present.(If

the


pass H2S

original solution is

green).

gas through it.


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+).


One Rupee Coin (India)-Made in 2010


Zero Group:

Add concentrated

solution of

No white fumes

observed. Ammonia(NH4

+) is absent.

sodium


Group I:



formed. Pb2+,Ag2+ and Hg2

2+ are absent.


original solution.

Group II:

Pb2+, Cu2+, As3+ are

absent.


HCl to

No black or yellow

precipitate


and pass formed.

H2S gas through it.

Group III:

Add NH4Cl and

NH4OH(in

A reddish brown

precipitate is Fe3+ may be present.


solution. obtained.

Confirmatory for

Fe3+:

Dissolve the reddish

brown

precipitate in dilute


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.


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+).


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


BIBLIOGRAPHY

LABORATORY MANUAL OF CHEMISTRY

WEBSITES —Www.thechemistryguru.com

Chemistry Project On Coin Analysisthechemistryguru.com/wp-content/uploads/2017/12/... · Chemistry Project On Coin Analysis . 2 ... project titled “Qualitative Analysis of Coins”.

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