• No results found

Investigatory Chemistry Project

N/A
N/A
Protected

Academic year: 2021

Share "Investigatory Chemistry Project"

Copied!
19
0
0

Loading.... (view fulltext now)

Full text

(1)

CHEMISTRY

PROJECT

S u b m i t t e d b y : - V a n d i t t C l a s s : - X I I ‘ B ’ R o l l n o : - 2 5

(2)

INDEX

1.Certificate 2.Acknowledgement 3.AIM 4.Apparatus 5.Introduction 6.Theory 7.Procedure -Colgate -Pepsodent -Close-UP

8.COMPARITIVE INFERENCE TABLE 9.Conclusion

(3)

Certificate

This is to certify that Vanditt, student of Class XIIth–B, Navyug School, Sarojni Nagar has completed the

project having aim “To Detect The Presence Of

Different Anions And Cations In Different Brands Of

Toothpaste” during the academic year 2013-14 towards

partial fulfillment of credit for the chemistry practical evaluation of CBSE 2014 and submitted satisfactory report as compiled in the following pages under my supervision.

Mrs. Taruna Sikri Department of Chemistry Navyug School, Sarojni Nagar

(4)

Acknowledgement

I owe thanks to many people who helped me in this project.

My deep thanks of gratitude are to Mrs. Taruna Sikri, our chemistry teacher for helping me in this topic with her valuable guidance.

Finally, I would also thank you my family members and friends for their constant support.

(5)

AIM

To Detect The Presence Of

Different Anions And Cations In

Different Brands Of Toothpaste.

(6)

Apparatus

Toothpaste(s):

Colgate, Pepsodent and Close-UP.

Chemicals:

Hydrochloric acid, dilute Sulphuric acid, concentrated Sulphuric acid, Barium chloride, Ammonium chloride, Ammonium hydroxide, Ammonium carbonate, Acetic acid, Nitric acid, Silver nitrate, Calcium chloride,

Pottasium Ferrocyanide, H2S gas.

(7)

Introduction

The invention of toothpaste has brought about a revolution in the field of dentology. Toothpaste and tooth powders are the substances used to clean teeth. Non cleaning of teeth can cause tooth decay, i.e., hole in the enamel or plaque. The dental enamel is the

hardest material in our body but is formed of calcium phosphate and it can be dissolved by acid. The

presence of specific bacteria metabolize some sugar to lactic acid and low resistance of the enamel to bacteria colonization is caused. Prevention of the dental plaque protects against the development of caries.

Toothpaste contain a mildly abrasive substance such as calcium carbonate and a detergent or soap, some sweetening agent other than sugar and flavouring oils to make it pleasant to taste and smell. Some

toothpaste contains fluorides which make the enamel surface of the tooth more resistant to bacterial activity and act against micro-organisms as a metabolic poison. Epidemological study in the US in the 1930’s and

1940’s have revealed an inverse relationship between the fluoride content of water and rate of dental

carriers. Generally any standard toothpaste contain calcium carbonate, sodium monofluoro phosphate, sodium lauryl sulphate, zinc sulphate, alum, some flavouring oils are also added.

(8)

A dentrifices is defined as a cleaning agent in the form powder, paste or liquid to be used on the tooth. The term does not include devices used in aid in cleaning process such as tooth brushes and dental floss. Modern dentrifice are an extension to numerous abrasives and cleaning substances used as dentrifices.

The primary function of a dentrifice is the mechanical cleaning of teeth. They prevent the accumulation of layers of mucous plaques that gives the appearance of yellow teeth. Dentrifices are functionally non antisepts but in cleaning teeth they serve as detergents of teeth and mucous membranes of the mouth. Dentrifices

remove accessible products of oral purification. Some dentrifices liberate ammonia, which reduce the

bacterial propagation in the mouth preventing the formation of mucous plaques.

Basic ingredients of a dentrifice are an abrasive and a detergent. However, other ingredients of the following categories are also added.

Flavours and sweetness to increase palatability

Lubricants are also used and emulsifiers or plasticisers such as glue.

Colouring agents are used for aesthetic appeal. Mucilage are used to affect homogeneity in case of toothpaste to facilitate expulsion from the tube. Special substances such as antiseptics and counter irritants are also used.

(9)

Theory

In qualitative analysis, the given compound is analysed for the radicals, that is, cations and anions that it

contains. The common procedure of testing on

unknown salt is to make its solution and then test this solution for the ions present in it. There are separate procedure for detecting cation and anion.

IDENTIFICATION OF ACID RADICAL (ANION)

The identification of acid radicals is first done on the basis of preliminary tests. They can be divided in to three categories each with separate group reagent. Therefore anion may be identified by performing the following tests in order given.

Dilute H2SO4 test

Concentrated H2SO4 test

Independent Group (SO42-, PO43-)

IDENTIFICATION OF BASIC RADICALS (CATION)

The basic radicals indicated in the preliminary test have to be confirmed by applying wet tests, The cations

have been divided into six groups with suitable group reagents. The classification of cations is based on the knowledge of solubility products of salts of these basic radicals. For adjusting the conditions of precipitation

(10)

another concept called common ion effect plays and important role.

COMMON ION EFFECT

Weak acids and weak bases are ionized only to a small extent in their aqueous solution. In their solutions, unionized molecules are in dynamic equilibrium with ions, the degree of dissociation of a weak electrolyte is further suppressed if some strong electrolyte which can furnish some ion common with the ions furnished by weak electrolyte is added to solution. This is called common ion effect.

Thus, the suppression of the degree of ionization of a weak electrolyte by the addition of some strong

electrolyte have a common ion, is called common ion effect.

(11)

COLGATE

ANION

S.NO. EXPERIMENT OBSERVATION INFERENCE

1. To the paste add dilute H2SO4 A colourless, odourless gas is evolved. CO32- may be present 2. To the sample add

MgSO4 solution.

A white ppt. is obtained.

CO32-

confirmed 3. To the sample add

concentrated H2SO4 No change Conc. H2SO4 group absent 4. (i) (ii)

To the sample add CH3COOH and CaCl2

Add dilute HCl A white ppt. is formed The ppt. dissolves F- present

5. To the sample add BaCl2 solution

A white ppt. is obtained

(12)

CATION

S.NO. EXPERIMENT OBSERVATION INFERENCE

6. To the sample add

NaOH and heat No change Group 0 absent 7. To the sample add

dilute HCl No change Group I absent 8. To the above test

tube add H2S

No change Group II absent 9. To the sample add

NH4OH and NH4Cl

No change Group III absent 10. To the above test

tube add H2S

No change Group IV absent 11. To the sample add

NH4OH, NH4Cl and

Solid (NH4)2CO3

A white ppt.

is obtained Group V absent 12. Dissolve the ppt. in

CH3COOH and

divide in to 3 parts (i) To the first part add

K2CrO4 solution

No change Ba2+ absent (ii) To the second part

add (NH4)2SO4

No change Sr2+ absent (iii) To the third part

add (NH4)2C2O4

A white ppt.

is obtained Ca

2+ present

13. To the sample add NH4OH and NH4Cl in excess. Add (NH4)2HPO4 A white ppt. is obtained Mg 2+ detected

(13)

PEPSODENT

ANION

S.NO. EXPERIMENT Observation Inference

1. To the paste add dilute H2SO4 A colourless, odourless gas is evolved CO32- detected 2. To the sample add

MgSO4 solution

A white ppt.

is obtained CO3

2-confirmed 3. To the sample add

conc. H2SO4

A colourless pungent gas is given off

Cl- detected 4. To the sample add

dilute HNO3, Boil,

cool and add AgNO3

A white ppt. is obtained Cl

-

(14)

CATION

S.NO. EXPERIMENT OBSERVATION INFERENCE

5. To the sample add

NaOH and heat No change Group 0 absent 6. To the sample add

dilute HCl No change Group I absent 7. To the above test

tube add H2S

No change Group II absent 8. To the sample add

NH4OH and NH4Cl A white ppt. is obtained Al 3+ detected 9. Dissolved the ppt. in dilute HCl. Add blue litmus. Now add NH4OH

A blue ppt. is obtained Al

3+

confirmed 10. To the above test

tube add H2S

No change Group IV absent 11. To the sample add

NH4OH and NH4Cl

and Solid (NH4)2CO3

A white ppt. is

obtained Group V absent 12. Dissolve the ppt. in

CH3COOH and

divide it into 3 parts

(i) To the first part add K2CrO4 solution

No change Ba2+ absent (ii) To the second part

add (NH4)2C2O4

A white ppt. is obtained Ca

2+ present

13. To the sample add NH4OH and NH4Cl in excess. Add (NH4)2HPO4 A white ppt. is obtained Mg 2+ detected

(15)

Close-UP

ANION

S.NO. EXPERIMENT OBSERVATION INFERENCE

1. To the paste add dilute H2SO4 A colourless pungent gas evolves which turns acidified potassium dichromate paper green SO3 2-detected

2. To the sample add BaCl2 solution

A white ppt. is

obtained SO3

2-

confirmed 3. To the sample add

concentrated H2SO4 No change Conc. H2SO4 group absent 4.(i) (ii)

To the sample add CH3COOH and CaCl2 Add dilute HCl A white ppt. is obtained The ppt. dissolves F- present

(16)

CATION

S.NO. EXPERIMENT OBSERVATION INFERENCE

5 To the sample add

NaOH and heat No change Group 0 absent 6. To the sample add

dilute HCl No change Group I absent 7. To the above test

tube add H2S

No change Group II absent 8. To the sample add

NH4OH and NH4Cl A brown ppt. is observed Fe 3+ detected 9. Dissolve the ppt. in

dilute HCl and add Potassium Ferrocyanide A prussian blue colour is obtained Fe3+ confirmed 10. To the above test

tube add H2S

No change Group IV absent 11. To the sample add

NH4OH, NH4Cl and

Solid (NH4)2CO3

A white ppt. is

obtained Group V present 12. Dissolve CH3COOH

and divide into three parts

(i) To the first part add K2CrO4 solution

No change Ba2+ absent (ii) To the second part

add (NH4)2SO4

solution

No change Sr2+ absent (iii) To the third part

add (NH4)2C2O4 and NH4OH A white ppt. is obtained Ca2+ present 13. To the sample add

NH4OH and NH4Cl in

excess and add (NH4)2PO4

(17)

COMPARITIVE INFERENCE

TABLE

NAME OF THE TOOTHPASTE F- Ca2+ CO32- SO32- Cl- SO42- Al3+ Fe3+ Mg2+ COLGATE PEPSODENT CLOSE-UP

(18)

CONCLUSIONS

For the ideal toothpaste, sodium, calcium, Magnesium, chloride and sulphate should be present.

On the basis of comparative inference table _________ is the best of all toothpaste as it contains most of the essential constituents of toothpaste.

(19)

Precautions

1. Handle chemicals carefully.

2. Use test tube holder to hold the test tube. 3. Never add water to conc. Acids

4. Never touch any chemical with hands directly. 5. Use a dropper for concentrated Acids.

References

Related documents

“I haven't taught a single lesson today, but at least my line is straight!” she cynically adds, underlining the dilemma she faces as an impossible teacher: The principal and

Also, because in traditional scalar tracking loss-of-lock might occur for an extended interval greater than five seconds at one receiver (e.g. Receiver Y for PRN

In patients who received aversion treatment for a drug of dependency (in addition to alcohol), the 1-year total abstinence rate for those contacted by phone and adding those

Mustialan- katu 3, 00790 Helsinki Alternative 5 Center for Eating Disorders, Fredrikinkatu 20 A 10, 00120 Helsinki, (Elina Saarinen) Alternative 6 Sydänliittto,

Jersey-based trustee (or Jersey- based manager where trust powers vested in the manager) Jersey limited partnership (managed from within Jersey): Jersey-based general partner. No

However if the mirror surfaces can withstand a chlorine gas environment corresponding to well over 45 years of exposure at a public indoor swimming pool

This link style is used at the end of any piece of content that you wish to link a reader to another area of the site that has additional content or related content..

This paper presents a Modified Distributed Bees Algorithm (MDBA) that is developed to allocate stationary heterogeneous sensors to upcoming unknown tasks using a decentralized,