NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 1 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.1
EXPERIMENT NAME: Redox Titration
Objective: -
Find out the percentage of Iron in a given iron alloy solution, when X grams of
alloy dissolved in 1 liter
Apparatus/Reagent Required :-
Burrette, Pippete, Conical flask, Funnel./
Std N/40 KMnO4 solution , dil H2SO4, Alloy solution.
Theory: To determine the amount of iron in alloy, the alloy sample is dissolved in dil. H2SO4, the iron present is
converted to ferrous sulfate with the liberation of hydrogen gas.
Fe + H2SO4 → FeSO4 + H2 ↑
The Fe2++ present in the solution can be determined by titration with a standard KMnO4 solution.
Potassium permanganate Oxidizes ferrous ion into ferric ion in acid medium in cold and is itself reduced
to colourless manganous ion.
MnO4- + 8H+ + 5e- → Mn2++4H2O
(Reduction)
[Fe2+ → Fe3+ + e-] X 5
MnO4- +5Fe2+ + 8H+ → Mn2+ + 5Fe3++ 4H2)
(Oxidation)
(Redox)
The appearance of a faint but permanent pink colour marks the end point.
Chemical Equation:2KMnO4 + 3H2SO4 → K2SO4 + MnSO4 + 3H2O+5[O]
[2FeSO4 + H2SO4 + [O] → Fe2 (SO4)3 + H2O] X 5
-----------------------------------------------------------------------------------------------2KMnO4+8H2SO4+10FeSO4→ K2SO4+2MnSO4+5Fe2 (SO4)3+8H2O
Procedure: 
Fill burette with KMnO4 solution.
Page 2 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry





Pipette out 10ml of the alloy solution into the conical flask.
To this add about 2ml of dilute H2SO4.
Now titrate it against KMnO4 solution drop by drop till the colour of the solution just changes to
permanent pink.
Note down the volume of KMnO4 used.
Repeat the titration with rest 10ml portion of the solution until concordant readings are
obtained.
Observation Table :S.No
Volume of alloy solution taken
Burette Reading
Initial
1
2
3
Concordant Reading =V2 ml.
Observation:Normality of KMnO4 solution
=N2=N/40
Volume of KMnO4 Used
=V2 ml
Normality of alloy solution
=N1
Volume of alloy solution in each titration
=V1=10ml
Calculation :Applying Normality Equation
N1V1 = N2V2
Page 3 of 43
Final
Volume
KMnO4 used
of
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
N1 X 10 = N/40 X V2
N1 = 1/40 X V2/10
Strength of alloy solution = Normality X Eq. Wt of Iron
(g/l)
= X gm/l
Percentage of Iron in alloy:Strength of Iron in g/l
=
…..…………………………
X
100
Amount of alloy dissolved in One-liter solution
Result:- Percentage of Iron in given alloy sample is =……..%
Precautions:1.
2.
3.
4.
5.
6.
7.
8.
All the volumetric apparatus should be washed with distilled water before use.
Rinse the burette with a solution of KMnO4 to be taken in the burette.
Rinse the pipette with a solution to be taken in the conical flask.
Wash the titration (Conical flask) with distilled water after every titration.
Titration is carried out at room temperature.
KMnO4 solution should not be added too fast.
Always filter KMnO4 solution through glass wool plug and not filter paper.
Do not use rubber pinchcock burette, as it is organic matter.
Suggestions:Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Page 4 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
1.
Engg. Chemistry
Author
Dr. Shashi Chawla
2.
Practical Chemistry Dr. Sudha Rani
3.
4.
5.
Web resources:
1.
2.
3.
4.
Page 5 of 43
Page No.
E-5 to E-22
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.2
EXPERIMENT NAME: Redox Titration
Objective: -
Estimation volumetrically the percentage of chromium in a given chrom alloy
solution when X gm of alloy dissolve in one liter.
Apparatus/Reagent Required :-
Burrette, Pippete, Conical flask, Funnel
Alloy solution, N/40 KMnO4 solution and N/40 Ferrous ammonium Sulphate solution.
Theory: -
Chromium can estimate directly by using potassium ferrocyanide K3[Fe(CN)6] or
diphenyl amine as an indicator but as the percentage of chromium in chrome alloy is less hence indirect
approach for analysis has been followed.
For the estimation of Cr it is first oxidized to dichromate, In presence of an acid, K 2Cr2O7 acts as
an oxidizing agent. The estimation is based on the principle that (F.A.S) can be quantitatively oxidized by
K2Cr2O7 (present in the solution). Thus when a definite amount of alloy solution is added to an excess
but known volume of standard F.A.S(Mohr Salt) solution then K2Cr2O7 oxidized Fe2++ to Fe3+
quantitatively.
K2Cr2O7 + 4H2SO4 → K2SO4 + Cr2 (SO4)3 + 4H2O + 3[O]
[2FeSO4 + H2SO4 + [O] → Fe2 (SO4)3 + H2O]
X 3
………………………………………………………………………..
K2Cr2O7 + 7H2SO4 + 6FeSO4 → K2SO4 + Cr2 (SO4)3 + 3Fe2(SO4)3 + 7H2O
The un-reacted ferrous ammonium sulphate in the solution is titrated with a standard KMnO 4 solution.
KMnO4 also oxidizes Fe2++(left in solution) to Fe3+++. When all Fe2++ changed into Fe3+++ then just an extra
drop of KMnO4 make the solution pink, the end point of titration.
2KMnO4 + 3H2SO4 → K2SO4 + 2MnSO4 + 3H2O + 5[O]
[2FeSO4 + H2SO4 + [O] → Fe2 (SO4)3 + H2O] X 5
……………………………………………………………………….
2KMnO4 + 10H2SO4 + 10FeSO4 → K2SO4 + 2MnSO4 + 5Fe2 (SO4)3 + 8H2O
Page 6 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: 





First of all take N/40 KMnO4 solution and fill it in the burette with help of funnel up to mark
zero. Remove the air bubble from the burette and funnel is also removed.
Pipette out 10 ml of F.A.S and transfer it in the conical flask. Pipette out 5 ml of chrome alloy
solution and transfer it in the same conical flask.
Cover the flask and allow to stand for 3 minutes.
Titrate the mixture of solution against N/40 KMnO4 solution.
As the end point comes it becomes light pink. Note the final burette reading.
Repeat the titration to get concordant reading.
Observation Table:S.No
Reaction Mixture
N/40 F.A.S
Alloy Solution
Volume of KMnO4
used (ml)
Burette Reading
Initial
Final
1
2
3
Concordant Reading=V1ml
Calculation:Normality of alloy KMnO4
=N1
Volume of KMnO4 used
= V1ml
Normality of F.A.S solution
=N2=N/40
Volume of F.A.S solution (Which react with KMnO4)
Normality of alloy solution(Unknown)
=V2 ml
= N3
Volume of alloy solution
=V3 ml
Page 7 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
N1V1 = N2V2
V2 = N1V1/N2
10-V2=V3(Which react the alloy)
N2V2 = N3V3
N3=
Strength of alloy solution=N3 X Eq. Wt.
(g/l)
=……gm/l
Strength of Cr alloy in g/l
Percentage of Cr alloy in g/l=
………………………........ ..............
X 100
Amount of alloy present in one litre
Results: The percentage of chromium in given chrom alloy solution is …….%
Precautions:1.
2.
3.
4.
The apparatus, which is used in titration, must be washed and dried carefully.
The air bubbles inside the burette must be removed after filling the N/40 KMnO4 solution.
The funnel must be removed over the burette.
When titrated the alloy solution against standard solution. The standard solution is added drop
by drop to get the exact end-point.
5. The reading should be taken carefully and properly.
Suggestions:-
Page 8 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 9 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.3
EXPERIMENT NAME: Iodometric Titration
Objective: - Estimation volumetrically the percentage of copper in a coper alloy solution when
X gm of alloy dissolved in one liter
Apparatus/Reagent Required :-
Burrette, Pippete, Conical flask, Funnel ,1
EDTA solution(M/100) ,2 Ammonium chloride-Ammonium hydroxide buffer(pH.10),3 Eriochrome BlackT- Indicator.
Theory: - In this method, copper is directly determined Iodometrically. When the alloy
sample is
dissolved in acid, the copper present is brought into solution in the form of cupric ions.
When an excess of KI is added to a copper solution an equivalent amount of iodine is liberated as per
the following reaction.
Cu + H2SO4 → CuSO4 + H2 ↑
CuSO4 + 2KI → K2SO4 + CuI2
2CuI2 → Cu2I2 ↓ + I2 ↑+ K2SO4
The reaction proceeds from left to right because of the insolubility of the cuprous iodide under
experimental condition employed. The liberated iodine can then be titrated with a std solution of
sodium thiosulphate using starch as an indicator.
Starch + I2 → Starch- Iodine Complex (Blue Colour)
I2 + 2Na2S2O3 →Na2S4O6 + 2NaI
Starch-Iodine-Complex + 2Na2S2O3 → Na2S4O6 + 2NaI + Starch
Disappearance of blue colour indicate the end point.
Page 10 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: 






Fill burette with hypo solution.
Pipette out 10ml of the given alloy solution in a clean Iodine value flask.
Add about 5 ml of 10% KI solution.
Cover the flask and allow to stand for 3 minute.
Titrate the liberated Iodine with hypo until the brown colour due to iodine change to a light
yellow. Add 1ml of starch indicator and continue the titration until the blue colour just fads out.
There is a tendency for the blue colour to return so that the first complete disappearance of the
colour for at least 10 sec in taken as the end point.
Repeat the titration to get concordant value
Observation Table:S.No
Volume of alloy
solution taken(ml)
Volume of Hypo
used(V2-V1)ml
Burette Reading
Initial(V1)
Final(V2)
1
2
3
Calculation:N1V1 = N2V2
Normality of alloy solution
=N1
Volume of alloy solution taken =V1
Normality of Hypo
=N2
Volume of Hypo used
=V2
Strength (Interm of copper) =Normality X Eq.wt of copper
Strength of copper in gm/l
Page 11 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Percentage of copper in alloy =………………………….. ………….. X 100
Amount of alloy dissolved in 1 Liter
Results: -
The percentage of Cu present in alloy solution is =………
Precautions:1.
2.
3.
4.
5.
Wash and clean the apparatus carefully before using them
Handle the apparatus carefully.
Note the reading carefully.
Appropriate amount of reagent should be used.
The flask should be shaken briskly during the titration.
Suggestions:-
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Page 12 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Web resources:
1.
2.
3.
4.
5.
Page 13 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.4
EXPERIMENT NAME:Complexometric Titration
Objective: - Find out the hardness of given water sample by complexometric method
Apparatus/Reagent Required :-
Burrette, Pippete, Conical flask, Funnel ,1
EDTA solution(M/100), 2 Ammonium chloride-Ammonium hydroxide buffer(pH.10), 3 Eriochrome BlackT- Indicator.
Theory: Though hard water is as palatable as soft water, knowledge of the magnitude and type of
hardness is important in determining the suitability of a water for domestic and industrial purposes. Use
of hard water for cleaning purposes is unsatisfactory as they increase the consumption of soaps. This
drawback has been partly overcome by the use of synthetic detergents but for personal hygiene. Soap
is preferred and hard water remain objectionable, Hard waters offer difficulties in dyeing of textiles are
uneconomical and even hazardous in steam generation and impart many of the undesirable
characteristics to the finished products in paper industry beverage, dairies and allied industries. Soft
water is required for an innumerable number of other industries. In devising an efficient and
economical softening process, determination of total hardness and the relative amounts of CH and NCH
and calcium and magnesium hardness is important.
Ethylene diamine tetra aceticacid is a well known complexing agent and it is generally used in
the form of di-sodium salt on account of their greater solubility. The di-sodium salt of EDTA ionises in
water to give 2Na+ ions and a strong chelating agent which for simplicity can be represented by H2Y2- . It
forms complexes with Ca2+ and Mg2+ and other divalent cat ions represented by the reaction.
H2Y2- + M2+ → MY2- + 2H+
( M2+ = Ca2+, Mg2+ )
The dissociation of these complexes is governed by the pH of the solution and the complexes with
hardness causing divalent ions are stable in alkaline medium(pH range 8-10).
{Buffer Solution: The optimum pH for the experiment is 10.0±0.1 and adjusted by Ammonium chloride
hydroxide buffer (pH 10)}
Eriochrome Black-T is used as an indicator in this analysis which is chemically known as:
{Sodium-1-(hydroxyl-2-napthylazo)-6nitro-2napthol-4-sulphonate}
Page 14 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
It has two ionisable phenolic hydrogen atoms and for simplicity is represented as Na+H2I- :
7.0
11.5
H2 In2-
↔
HIn2-
(Red)
5.5
(Blue)
In3-
↔
(Yellowish Orange)
In pH range 7-11 the Indicator reacts with the metal ion to form a weak complex.
When a small amount of the indicator solution is added to a hard water sample whose pH has been
controlled by the addition of the buffer soluition. The indicators reacts with Mg2+ to produce wine red
colour.
Mg2+ + HIn2- =
Mg In2-
+
H+
(Wine red colour)
As EDTA is added, free Ca2+ ions are first complexed to form Ca EDTA Complex this being the most stable
complexes :
Ca2+ + H2Y2- = CaY2- + 2H+
Free Mg2+ ions then react to give Mg-EDTA complexes which is less
Mg2+ + H2Y2- = MgY2- + HIn2- + 2 H+
(Wine red)
(Pure Blue)
Stable than Ca-EDTA complex but more stable than Mg- Indicator complex. Therefore if an extra drop of
EDTA is added after all the freee Ca2+ and Mg+ ions have been complexed. EDTA takes up Mg2+ from the
weak Mg –Indicator and leaving indicator in the free form:
MgIn2- + H2Y2- = MgY2- + HIn2- + H+
Completion of the above reaction (sharp colour change from wine red to blue) makes the end point of
the titration.
Page 15 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
HOOCCH2
CH2COOH
N-CH2-CH2-N
HOOCH2C
CH2COOH
Ethylene di-amine tetra acitic acid
-
OOCH2C
CH2COOH
N-CH2-CH2-N
CH2COO-
HOOCH2C
di-sodium salt of EDTA.
Procedure: 




Pipette out X ml of hard water sample into a conical flask,
Add 1ml buffer solution and 2 drops of the indicator.
Titrate against EDTA till the wine red colour changes to pure blue.
Record the volume of EDTA used as A ml.
This corresponds to the total hardness of the water sample.
Observation Table:S.NO
VOLUME OF WATER
SAMPLE TAKEN
BURETTE READING S
INITIAL(V1)
1
2
3
Concordant reading ………….ml
Calculation:-
Page 16 of 43
FINAL(V2)
VOLUME OF
EDTA(V2-V1)
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
1Mole EDTA
= 1Mol Ca2+
1ml of 1M EDTA = 100mg of CaCO3
1ml of .01 EDTA = 1mg of CaCO3
A ml of .01M EDTA = A mg of CaCO3
Hence
The total hardness present in Xml of the water sample taken =A mg of CaCO3
The hardness present in 1000ml of water sample = A X 1000/X mg of CaCO3
=………………..mg of CaCO3
=………………..mg/l or ppm
S.NO
VOLUME OF WATER
SAMPLE TAKEN
BURETTE READING S
INITIAL(V1)
1
2
3
Concordant reading ………….ml
Results: -
Page 17 of 43
FINAL(V2)
VOLUME OF
EDTA(V2-V1)
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Hardness present in given water sample is …………..
Precautions:1 No tings of reddish blue should remain at the end point.
2 The solution should be clear blue.
3 Titration should be performed slowly near the end point.
Suggestions:Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
Page 18 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.5
EXPERIMENT NAME: Acid-Base Titration
Objective: - Determination of alkalinity of a water.
Apparatus/Reagent Required :- :-
Burrette, Pippete, Conical flask,
Funnel, , N/20 HCl, Phenolphthalein Indicator, Methyl Orange Indicator.
Theory: Alkalinity of natural water may be attributed to the presence of salts of weak acids such as bicarbonates,
Phosphates, Silicates and borates which induces buffer capacity and resists the lowering of PH. Surface
waters containing algae and also water treated by lime soda process may contain considerable quantity
of carbonates and hydroxide alkalinity. Highly alkaline water may lead to caustic embitterment and also
may cause deposition of precipitates and sludges in boiler tubes and pipes. For water softening process
as well as boiler feed water analysis it is essential to have an idea about the nature and extent of
alkalinity present.
- The alkalinity of water can be considered to be mainly due to
1. Hydroxides
2. Carbonates
3. Bi carbonates
With respect to the constituents causing alkalinity in natural water the following situation may arise
1.
2.
3.
4.
5.
Hydroxides
Carbonates
Bi carbonates
Hydroxides and Carbonates
Carbonates and Bicarbonates
The possibilities of hydroxides and bicarbonates existing together is rules out owing to the fact that they
combine with each other forming the respective carbonates
OH- + HCO3– → CO32- + H20
Page 19 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
The type and extent of alkalinity present in a water sample may be conveniently determined by titrating
an aliquot of the sample with a standard acid to phenolphthalein end point[p] and then continuing the
titration to methyl orange end-point [M], the reaction taking place may be represented by the following
equation.
OH- + H+ → H2O
CO3 2- + H+→ HCO3HCO3-+ H+→ H2CO3
P
↔
M
H2O+CO2
The volume of acid run down up to phenolphthalein end-point [p] corresponds to the completion to
equation (1) and (2) given above while the volume of acid run down after [P] corresponds to the
completion of equation (3). The total amount of acid used from the beginning of the experiment i.e. [M]
corresponds to the total alkalinity and represents the completion of reaction shown by equation (1) to
(3).
The result may be summarized in the following table from which the amount of hydroxides, Carbonates
and Bicarbonates present in the water sample may be computed.
Result of titration to
phenolphthalein end point
[P] and methyl orange endpoint [M].
P=M
P=0,M
P=1/2M
P<1/2M
P>1/2M
Hydroxide[OH-]
Carbonates[CO32-]
Bicarbonates[HCO32-]
M
NIL
NIL
NIL
2P-M
NIL
NIL
2P OR M
2P
2(M-P)
NIL
M
NIL
M-2P
NIL
Alkalinity is generally expressed as parts per million in terms of CaCO3.
Page 20 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: 




Transfer X ml of the water sample in to a conical flask.
Add few drops of phenolphthalein indicator and titrate the sample with the standard HCl until
the pink colour just disappear.
Note the titer value as the phenolphthalein end-point,[P].
Add 2 to 3 drops of methyl orange indicator to the same solution and continue the titration until
a sharp colour change from yellow to red take place.
Note the total titer value from the beginning of the experiment as methyl orange end-point,[M].
Observation Table:-
S.No
Volume of the water
sample taken
Phenolphthalein end-point[P].
1
2
3
Calculation:Observation:Normality of a HCl
=N2=N/20
Volume of HCl
=V2 ml
Normality of water sample
=N1
Volume of water sample
=V1=10ml
Calculation :Applying Normality Equation
N1V1 = N2V2
N1 X 10 = N/20 X V2
N1 = 1/20 X V2/10
Page 21 of 43
Methyl orange end-point,[M].
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Strength of alloy solution = Normality X Eq. Wt CaCO3
(g/l)
= X gm/l
Results: Result:- Alkalinity of the given water sample is =………PPM
Precautions:1. The glass apparatus should be perfectly cleaned before the start of the experiment.
2. Since phenolphthalein and methyl orange indicator are used in determination of alkalinity the
end point of the titration should be observed carefully.
Suggestions:Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
Page 22 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.6
EXPERIMENT NAME: Redwood Viscosity calculation
Objective: - Determination of the viscosity of a given oil sample by Redwood Viscometer.
Apparatus/Reagent Required :-
Two thermometer, 50ml Recovery flask,
Beaker, Stopwatch, Oil Sample, Redwood Viscometer.
Theory: It is the most important property, which is considered while selecting a good lubricant for a particular
application. It is the measure of internal resistance of the fluid i.e. Resistance the flow or movement of
one layer over another, this property of liquids is termed as viscosity. Viscosity is one of the most
important properties of lubricating oil. The formation of a fluid film of lubricant between the frictional
surfaces, the generation of frictional heat under particular condition of load, bearing speed and
lubricant supply most depend upon the viscosity of the oil. If the viscosity of the oil is too low, a liquid
oil film cannot be maintained between two moving/sliding surfaces and consequently excessive wear
will take place, On the other hand, if viscosity of lubricating oil is too high, excessive friction due to the
shearing of oil itself would result. Hence it is essentials to have the complete knowledge of the viscosity
of lubrication oil.
The redwood apparatus measures viscosity in empirical units and not in absolute unit such as
centistokes. There are two type of redwood viscometer i.e. Redwood No1 and Redwood No2. The
Redwood No1 will correctly indicate the viscosity for liquid having flow time between 30 seconds to
2000 seconds. If the flow time measured with this apparatus for any oil exceed 2000 second the test
should be repeated with Redwood Viscometer No.2 which will give the correct value of viscosity for such
highly viscous oil.
DISCRIPTION OF APPARATUS:It consist of
1 An Oil Cup
2 A water Bath Accessories
3 Two Thermometer
Page 23 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
4 A suitable Stand
The oil cup is a silvered copper cup which consists of a pointer to indicate the oil level to which the oil is
to be filled and a gate jet (1.62mm dia) which is completely closed when the ball valve is lifted (Cup
dimensions 190mm height and 46.5 m diameter) Water bath is made of brass and surrounds the oil cup.
It is heated electrically. It is provided with a tap for emptying water, Stirring of the water in bath is
affected by means of a cylinder surrounding the oil cup which is provided by four blades.
Two thermometers to read the temperature of oil and water are provided. The apparatus rests on a
tripod stand with leveling screw, so that the 50ml, receiving volumetric flask can be placed beneath the
jet to catch and measure the oil flowing from the jet.
Fig. Redwood Viscometer
Page 24 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: 










Viscometer was leveled by adjusting the leveling screws.
The water bath was then filled roughly at the same time level as of the oil in cup.
Ball valve was then placed in the cup.
Oil was then poured into the cup up to the pointer.
The two thermometers were inserted to record the temperature of oil and water,
the bath was then heated electrically which in turn heated the oil.
Stirrings was done to keep the water bath temperature uniform
At a constant temperature oil and water.
The ball valve was raised and stop watch was started immediately.
Time required by the 50ml. Of oil to flow out was noted.
Viscosities at various temperatures were calculated by using the formula.
Observation Table:S.No
Temperature
o
C
Flow Time of 50 ml
oil sample in sec
1
2
3
Calculation:Viscosity of sample oil can be determine by using following formula
η=AT-B/T
Where,
η =Viscosity in stokes
T=Time in second
A, B= Constant for apparatus
Page 25 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
(A) =0.264 and (B)=190,when t=40 to 85 seconds
(A)=0.247 and (B) =65, when t=85 to 2000 seconds
100 Centistokes=1stoke
Unit Conversion: Stoke X Density=Poise (Absolute Density)
1Poise=100 Centipoises
Results: Viscosity of the given oil sample is .............
Precautions:1. Apparatus should be well leveled.
2. Oil should be noted free from the suspension.
3. Time should be noted accurately
4. The water in the bath and the liquid in the inner jacket should be properly stirred so that the
difference in the temperature of water and oil is not mere than 20C.
5. The watch should be stopped accurately at the time when oil level in measuring flask is reached to
mark.
6. The flask should be placed slightly away from the center of the hole in cup so that there should not be
any froth formation inside the flask.
Suggestions:-
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Page 26 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 27 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.7
EXPERIMENT NAME: Flash and Fire Point
Objective:
To determine the flash & Fire point of the given oil sample by Pensky Martin
apparatus.
Apparatus/Reagent Required :-
Sample Oil, Pensky Martin Apparatus.
Theory: Flash Point: - The flash point is the lowest temperature at which sufficient vapour is given off by oil to
cause a momentary flash as the vapour come in contact.
Fire Point:- The fire point is the lowest temperature at which sufficient vapour are given off by an oil so
that it burns continuously for at least five seconds on being lighted by a test flame.
Theory: - A fire may develop if a set of the following three conditions ‘Fire Triangle’ is simultaneously
satisfied.
1. A source of ignition.
2. Oxygen (Present in air).
3 Combustion vapour within the explosive range.
Good lubricating oil should not volatize under the working temperature even if some volatization takes
place, the vapour formed should not form inflammable mixture with air under the conditions of
lubrication.
Significance:The knowledge of flash & fire point is helpful in providing safeguard against fire hazard during their
storage transportation handling and use. They are also of immense importance for illuminating oil to
ensure safety. Flesh point of illuminating oils (e.g. Kerosene) should be reasonably above the average
maximum atmosphere temperature of a country. Liquid & oil with flash point above 140 o F are called
combustible liquid. Although flash point and fire point are used for comparative rating of the fire hazard
potential of different flammable liquids and for labeling their containers accordingly. Flash & Fire point
has also been used to detect solvent contamination.
Page 28 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Description of apparatus: - this instrument is used generally for all petroleum products having a flash
point above 48o C. It consist an oil cup (about 5 cm in diameter & 5.5 cm deep). The level to which oil is
to be filled is marked inside the cup. The cup lid is provided with few opening of standard sizes.
Through one of these passes a thermometer, while the second opening is used for introducing test
flame.
Through third opening passes stirrer carrying two steel blades while the fourth is meant for admission of
air.
At the top of the cup a shutter (lever Mechanism) is present. By moving the shutter opening in the lid
opens & flame (Carried by a flame explosive device) is dipped into this opening thereby bringing the
flame over the oil surface. The apparatus also consist a flame explosive device, which is a tiny flame
connected to the shutter by a lever mechanism & also a pilot burner( As the test flame in introduced in
the opening, it gets extinguished, but when the test flame is returned to its original position, its
automatically lighted by the pilot burner.
The oil cup is seated in an air bath covered by a curved top, plate of brass & below the heating bath is an
iron ring covered with gauge.
Procedure: -
Page 29 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry








The oil cup is cleaned and dried and the oil is then poured in up to the level indicated by the
filling mark. The lid is placed in position;
The thermometer is inserted in the holder, and the cup is set in the air bath. T
he apparatus is heated at the rate of from 5 to 6 o C rise per minute and stirrer is rotated from 1
to 2 revolutions per second, Below the flash point,
The test flame is applied in such a manner that the flame is lowered in one half second, left in its
lowered position for one second and quickly raised.
While the test flame is being applied, stirring is stopped.
When the flash Point is nearly reached a blue halo is often observed round the test flame, but
this is not the actual flash.
The temperature at which a distinct flash is visible in the two observation ports is recorded as
the flash Point.
After knowing the flash point the oil is heated continuously and the application of the test flame
is done after every 1o C rise in temperature of oil, at certain temperature the oil will ignite and
continue to burn for a period of at least 5 seconds are recorded as fire point.
Observation Table:S.No
Temperature
o
Flash Point
Fire Point
C
1
2
3
Results: Flash point and Fire Point of the given oil sample is .............
Precautions:1.
2.
3.
4.
5.
The oil must be stirred continuously.
Oil is poured up to the level indicated by filling mark in the cup.
While the test flame is being applied, stirring is stopped.
Care being taken that no traces of any low flash material is present in the given oil sample.
When gas oil or fuel oil is to be tested, the sample must first be dried.
Page 30 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Suggestions:-
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 31 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.8
EXPERIMENT NAME: Flash and Fire Point
Objective: To determine the flash & Fire Point of the given oil sample by Abel’s Apparatus.
Apparatus/Reagent Required :-
Sample oil, Abels Flash &Fire point
apparatus.
Theory: Theory: - A fire may develop if a set of the following three conditions ‘Fire Triangle’ is simultaneously
satisfied.
1. A Source of ignition.
2. Oxygen(present in air)
3. Combustible vapour with in the explosive range.
Good lubricating oil should not volatize under the working temperature even if some volatization takes
place, the vapour formed should not form inflammable mixture with air under the conditions of
lubrication.
Significance:The knowledge of flash & fire point is helpful in providing safeguard against fire hazard during their
storage transportation handling and use. They are also of immense importance for illuminating oil to
ensure safety. Flesh point of illuminating oils (e.g. Kerosene) should be reasonably above the average
maximum atmosphere temperature of a country. Liquid & oil with flash point above 140 o F are called
combustible liquid. Although flash point and fire point are not used for comparative rating of the fire
hazard potential of different flammable liquids and for labeling their containers accordingly. Flash & Fire
point has also been used to detect solvent contamination
Description of Apparatus:Abels Flash & Fire point Apparatus consist a cylindrical brass oil cup and the lid provided with a paddle
stirrer. It also have an opening for a thermometer, an arrangement for applying a small test flame &
three small opening , one for the application of test flame and the other two for the entry of the air into
the oil covered by a sliding shutter.
Page 32 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
The cup is supported by its flange over a copper air jacket, which is enclosed by cylindrical vessel made
of copper.
Procedure: At first given sample oil is filled in the oil cup. Now water is filled in the jacket till it comes out the outlet.
This arrangement is provided for indirect heating for more volatile oil (having low flash point).
Thermometer is fitted to note the temperature of the water bath and of oil sample.
Now the assembly is kept on an electric heater, which can be heated in a controlled manner when the
temperature of the oil reaches below 15o F of the probable flash point,
first application of the test flame is made by pulling the sliding shutter outwards so that the test flame
drips in to the central opening in the lid & comes in contact with the ascending vapour air mixture
subsequently the test flames applied at every 2o F rise of temperature.
The lowest temperature at which oil cause momentary flash are recorded as a flash point After knowing
the flash point the oil is heated continuously and the application of the test flame is done after every 1 o
Page 33 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
C rise in temperature of oil, at certain temperature the oil will ignite and continue to burn for a period of
at least 5 seconds are recorded as fire point.
Generally the fire point of oil is about 5o to 40o C higher than its flash point.
Observation Table:S.No
Temperature
o
Flash Point
Fire Point
C
1
2
3
Results: The flash point of given oil sample is…….
The fire point of given oil sample is…….
Precautions:1. As moisture affects the flash point all parts of the cup and its accessories should be dried before
placing oil in the cup.
2. No oil should remain between the sliding and fixed plate forming the cover of the cup. If
necessary these should be separated and cleaned. Care should also be taken to prevent wetting
of the cup above the pointer tip.
3. With very low flashing oils the sample (sometimes the oil cup itself) may be cooled in melting ice
before filling.
4. Always a fresh portion of the oil sample should be used. A second determination on the same
portion of the oil shows a higher flash point.
5. The thermometer bulb should dip into the oil.
6. For applying the test flame, the slide should be drawn open slowly and closed quickly.
7. Stirring should be discontinued during the application of the test flame.
Page 34 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Suggestions:-
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 35 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.9
EXPERIMENT NAME: Cloud and Pour Point
Objective: - Determination of cloud and Pour Point of a given lubricating oil.
Apparatus/Reagent Required :-
Cloud and Pour Apparatus, Testing Oil.
Theory: Definition: - When oil is cooled slowly, the temperature at which it becomes cloudly or hazy in
appearance, is called its “Cloud Point”, while the temperature at which the oil ceases of flow or pour is
called its “Pour Point”
Significance: - Cloud and Pour point indicate the suitability of lubricants in cold conditions. Lubricant
used in a machine working at low temperatures should possess low pour point; otherwise solidification
of lubricant will cause jamming of the machine.
Theory: - Lubricating oils derived from petroleum usually contain dissolved paraffin wax and other
asphaltic or resinous impurities, their amounts depending on the efficiency of dew axing and refining
processes used. These impurities tend to separate out of the oil at lower temperatures. When a
petroleum oil is chilled under specified conditions, the temperature at which paraffin wax or other
solidifiable materials, normally dissolved in oil begin to separate out from solution in the form of minute
crystals, causing the oil to become less transparent, cloudy or hazy in appearance, is known as the
cloud point of the oil.
If the cooling is continued further, the amount of the separating material increases and a stage is
reached when the oil solidifies and stops flowing. The lowest temperature at which oil will flow or pour
under prescribed conditions, when it is cooled undisturbed at a fixed rate, is called its pour point.
The cloud point determination is limited only to transparent oils; otherwise there may be slight variation
in result due to the human error involved, since the decrease in transparency is to be visually observed.
Page 36 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: Cloud and pour point of lubricating oil is determined with the help of cloud and pour point apparatus.
It consists essentially of a flat bottomed tube about 3 cm in diameter and 12 in height enclosed in an air
jacket.
This tube is placed in a glass jar having suitable freezing mixture (Ice &CaCl2) and a thermometer.
The oil is first dried by shaking it with small amount of anhydrous and sodium sulphate and its is filtered
through lint less filter papers.
This oil is filled up to the mark inside the flat bottomed glass tube and the cork is then fitted.
Thermometer should dip inside the oil.
The tube is then kept in the freezing mixture. The temperature of the oil falls on cooling.
The tube is then taken out of the freezing mixture after every one degree centigrade fall in temperature
and then inspected for moment.
It is restored if the cloudiness has not formed.
The temperature is recorded as cloud point at which on inspection cloudiness in the oil is witnessed. For
determining pour point, cooling is further continued.
After every 3o C fall of temperature, the tube is with drawn and tilted to see the flow of the oil for 30
second.
If there is some movement of the oil the test tube is replaced immediately in the jacket.
The reading in the thermometer is recorded as pour point, when on observation no movement of oil is
observed.
Page 37 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Observation Table:S.No
Temperature
o
C
Cloud and Pour
Point
1
2
3
Results: 1. The Cloud Point of the given lubricating oil=………
2. The Pour Point of the given lubricating oil=……….
Precautions:1.
2.
3.
4.
The observation of tube should be completed with in ¾ seconds.
A suitable freezing mixture is chosen far particular lubricating oil.
The flat bottomed tube should not be kept directly in the freezing mixture.
While noting down the pour point, great care should be observed in; not disturbing the mass of
the oil which may lead to delay in solidification.
Suggestions:-
Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Page 38 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 39 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
EXPERIMENT NO.10
EXPERIMENT NAME: Aniline Point
Objective: - - To determine the aniline point of given lubricating oil.
Apparatus/Reagent Required :-
Aniline Point Apparatus, Testing Oil,Aniline.
Theory: The tendency of the lubricating oil to mix with aniline is expressed in terms of Aniline point. Aniline
Point is the minimum equilibrium solution temperature for equal volumes of aniline and lubricating oil
sample.
A lower aniline point of the lubricating oil means a higher percentage of aromatic hydrocarbons in it.
Since aromatic hydrocarbons have tendency to dissolve the rubber seals used in the system to prevent
leakage. Thus higher aniline point of lubricating oil is desirable.
1
Aniline Point of lubricant
X
…………………………………..
Aromatic contents of lubricant
The aniline point of the lubricating oil is determined by thoroughly mixing equal volumes of oil sample
and aniline in a test tube and heating the mixture on hot bath until a homogenous solution is obtained,
then the test tube is allowed to cool at controlled rate. The temperature at which lubricating oil and
aniline phases separate out is recorded as the aniline point.
Page 40 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Procedure: Clean and dry the apparatus, take 10 ml of aniline and 10 ml of oil sample in the air jacketed tube fitted
with stirrer and thermometer.
The mixture of aniline and oil sample is stirred and heated on hot bath to get a homogenous solution.
The rate of heating should be 1 to 2oC per min.
Now the homogenous mixture of oil & aniline is allowed to cool at the rate of 1o C per min and observe
the temperature at which two phases of the mixture are separated out or cloudiness or haziness in the
solution is obtained which shows the aniline point of the given oil sample.
Page 41 of 43
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
Observation Table:S.No
Temperature
o
Aniline Point
C
1
2
3
Results: The aniline point of the given lubricating oil is ……..o
Precautions:1. The apparatus and all the reagents must be perfectly dried.
2. Aniline being highly toxic so it should be taken with a pipette provided with rubber suction bulb.
3. Aniline being hygroscopic, water should not use in hot bath.
Suggestions:Lab Quiz :(10 Objective type questions related with experiment / software
program executed working principle & application.)
Further reading resources:
Book: Lab experiment related theory available in following
books:
Book Name
Author
1.
Page 42 of 43
Page No.
NAME OF LABORATORY: Engg. Chemistry
LAB SUBJECT CODE: BE-101
NAME OF DEPARTMENT: Engg. Chemistry
2.
3.
4.
5.
Web resources:
1.
2.
3.
4.
5.
Page 43 of 43