Title

Aim

Apparatus

Chemicals

Theory

Procedure

Observations

Expt. No. Date:

Determination of Acid Value of the lubricant.

To Determine acid value or neutralization number of the lubricant.

Burette stand, burette, pipette, conical flask, beaker etc.

0.01 N KOH (approximate), 0.01 N HCl, phenolphthalein indicator, distilled water

etc.

Most of the fatty acid contains free acid. High acidity indicates oil has been

oxidized and hence roughly it is an indicator for the age of the oil or it gives an idea

how old the fatty oil is.

From this information we can predict the stage at which lubricating oil should be

replaced. The acid value of the lubricating oil is defined as the milligrams of KOH

required to neutralize amount of free acid present in the one gm. of the oil .

PART : ( I ) STANDARDISATION OF KOH SOLUTION

Pipette out 25 ml of 0.01 N KOH in a 250 ml conical flask. Add 4 – 5 drops of

phenolphthalein indicator and titrate against 0.01 N HCl from the burette till it

becomes pink to colorless. Take three constant burette readings.

PART ( I )

Solution in Burette : 0.01 N HCl solution.

Solution in Conical Flask : 25 ml of Standard KOH solution + 1 – 2

drops of phenolphthalein indicator

Indicator : phenolphthalein indicator

End Point : Pink to colorless.

Pilot Reading : -----------ml. to ---------- ml.

Observation

Table

Calculations

Procedure

Observations

PART – ( I )

Sr.

No.

Initial B.R.

(ml)

Final B.R.

(ml)

Difference

B.R. (ml)

C B.R.

(ml)

1

2

3

PART ( I )

25 ml of standard KOH solution required X ml of 0.01 N HCl solution.

Therefore normality of KOH = 0.01 x X / 25

PART : ( II ) DETERMINATION OF ACID VALUE

Take a dry and clean 250 ml conical flask and weight accurately. Then add 5 ml of

the lubricating oil. The difference in weight will be the actual weight of the oil.

With the help of pipette add accurately 25 ml of 0.01 N KOH in the conical flask

and shake vigorously to dissolve the oil. Add few drops of phenolphthalein

indicator and titrate against N/100 HCl solution till the endpoint goes from pink to

colourless.

PART ( II )

Solution in Burette : 0.01 N HCl solution.

Solution in Conical Flask : 25 ml of 0.01 N KOH solution + 1 – 2

drops of phenolphthalein indicator

Indicator : phenolphthalein indicator

End Point : Pink to colorless.

Pilot Reading : -----------ml. to ---------- ml.

Observation

Table

Calculation

Result

PART – ( II )

Sr.

No.

Initial B.R.

(ml)

Final B.R.

(ml)

Difference

B.R. (ml)

C B.R.

(ml)

1

2

3

PART ( II )

Volume of N/100 KOH used to neutralize free acid in the lubricating oil = ( X – Y ) ml

Acid value of the oil = volume of KOH used x normality of KOH x 56 / wt. of the

sample.

= ---------------- mg/gm.

1) Normality of KOH = ------------------- N.

2) Acid value of the Oil = ------------------- mg/gm.

Title

Aim

Apparatus

Chemicals

Theory

Chemical

Reaction

Expt. No. Date:

Determination of Ferrous Ions.

To determine of ferrous ions in a given sample Spectrophotomatrically or

Colorimeter.

Colorimeter, beaker, weighing balance, measuring cylinder.

Conc. HCl , 10% Hydroxylamine Hydrochloride Amine acetate, 0.25%

Phenonthrolene solution, stock iron solution, distilled water.

Colorimeter is an instrument used to measure concentration of ions in solution.

The colour developed is proportional to the concentration

of the ions, hence the absorbance of the light is propartional to the ion

concentration the visible region is 400 – 700 nm light from a bulb falls preselected

filter, the light coming out is monochromatic and it falls on the sample in the quiet.

Some light is absorbed by the ions of the sample, depending on its concentration,

while the rest fall on photo cell. The photo cell converts light into current, this is

amplified and read as OD (Optical Density) or % t (Transmittance)

Ferrous ions forms a soluble chelated complex (orange, red colour) with

1,10 phenonthrolene. Using various concentration. The concentrations of Fe2+ ions

are determined.

Graph

Procedure

1% stock solution of ferrous ion is prepared.

Transfer 1 ml in a 50 ml standard flask. Add 5 ml each of 10% hydroxylamine

solution, sodium acetate solution and O – phenonthrolene solution in order. Dilute to

50 ml with distilled water and mix properly. Repeat the same with other

concentrations ( 2ml, 5ml, 10ml and unknown sample) keep coloured solutions at

rest for five minutes. Note down the absorbance in a spectrophotometer selecting

wavelength of 510 – 515 nm. Prepare standard calibration curve by plotting

absorbance against concentration of five standard solutions. The concentration of

unknown solutions. Which corresponds to the absorbance is determine from the

curve.

Observation

Table

Calculation

Sr. No. Concentration of Fe Solution Absorbance

1/a1 1mg/l

2/a1 2mg/l

3/a1 3mg/l

4/a1 4mg/l

5 unknown

A = abc

Where A = absorbance

a = molar extinction coefficient

b = path length of solution

c = concentration of solution

hence a1 =

a2a3a³

Result

For unknown a =

hence C =

hence c = --------------------- mg/l

The concentration of ferrous ions in the given sample is --------mg/lit.

Title

Aim

Apparatus

Chemicals

Theory

Procedure

Expt. No. Date:

Melting Point of Polymer.

To determine melting point / glass transition temperature of the given polymer.

Thermometer, oil bath, hotplate etc.

Polymer.

The temperature at which the polymer or any substance changes from solid to

liquid state at N.T.P. is called its melting point.

Glass Transition temp (Tg). Its conveniently measured in laboratory

by dilatometer. (i) Amorphous polymer, when called below certain

temperature becomes hard, brittle and glassy. But above this temperature they

are soft flexible and rubbery. This Transition Temperature of polymer is called

as glass transition temperature.

Fill the capillary with powdered polymer and attached it to the thermometer

with the help of thread and insert it in a oil bath, properly with the help of

stand. Heat the oil bath on a burner and note the melting temperature of

polymer.

Diagram

Result

Melting point of the given polymer is = -------------------- 0C

Title

Aim

Apparatus

Chemicals

Theory

Procedure

Diagram

Expt. No. Date:

pH of unknown solution.

To determine the pH of solution using pH meter .

Digital pH meter, calomel electrode, reference electrode, beaker, stirrer, etc.

Distilled water, buffer solution, (pH 4 and 9.2 pH ) unknown solution of acid, and

alkali.

The pH of a solution is defined as “the logarithm of the reciprocal of [H+] ion

concentration.

pH = log 1/[H+]

the pH of acdic solution can be directly determined by pH meter.

Standardize the pH meter with acidic buffer (pH4) solution as above. Wash the

electrode with distilled water and dry. Take 50 ml of HCl solution in a beaker and

dip the electrode completely into it. Note the pH of pure acidic solution and repeat

the same procedure for alkaline solutions.

Observation

Table

Result

Sr.

No.

Reading with

known buffer Sample No.

pH value on

meter Remarks

1 1

2 2

3 3

4 4

5 5

pH of unknown solution ( No. ) = --------------

Title

Aim

Apparatus

Chemicals

Theory

Chemical

Reaction

Expt. No. Date:

Estimation of Hardness.

To estimate and calculate the Hardness in given sample of water.

Burette, pipette, conical flask, burette stand, beaker, test tube.

Standard hard water, hard water sample,0.01M. EDTA solution, buffer solution

of pH = 10, Eriochrome Black T indicator.

The estimation of water hardness as applied to boiler water and other water is of great

interest for the chemical industries in general. It is an important factor in the

manufacturing of sugar, leather, pharmaceuticals, and food processing, Gum, Textiles

industries etc.

Hardness in water generally prevents The lathering of soap. This is due to the presence

of dissolved salts of Calcium, Magnesium, etc.

2C17H35 COONa + Ca+2 or Mg+2 (C17H35 COO)2 Ca or Mg + 2NaCl

Hardness can be classified as either temporary or permanent

hardness. Temporary hardness is caused by soluble bicarbonates of Calcium and

Magnesium. Permanent hardness is called by soluble Chlorides, Nitrates and Sulphates

of Calcium, Magnesium and other heavy ions. Temporary hardness can be removed by

boiling.

2Ca(HCO3)2 2CaCO3 + H2O.

Hard water forms scales in the boiler which is poor conductor of heat and electricity

hence causes wastage of fuels and danger of explosion.

CaCO3 +2HCl CaCl2 + H2O + CO2

Ca++ + Na2 C10H14O8 N2 Ca C10 H14 O8 N2 + 2Na

Mg++ + Na2 C10 H12 O8 N2 Mg C10 H14 O8 N7 +2Na

Procedure

Observations

Observation

Table

Calculations

PART – ( I ) Preparation of Standard Hard Water.

1. Dissolved 1 gm of CaCO3 in 10 ml of conc. HCl. Stir it well to get a clear

solution. Dilute the solution to 1 liter with distilled water 1 ml. [ 1 ml = 1 ppm

of CaCO3 ].

2. Pipette out 25 ml of it in a 250 ml conical flask. Add 5 to 10 ml of buffer

solution and 3 to 4 drops of EBT indicator to it.

3. Shake well and titrate the solution with 0.01 M of EDTA from the burette. End

point will be from red to blue in colour. [Dissolve 0.931 gms of EDTA in 250

ml of distilled water to make 0.01 M of EDTA solution.] This reading say X ml

gives the hardness due to CaCO3.

PART – ( I )

Solution in Burette : 0.01 M EDTA solution.

Solution in Conical Flask : 25 ml of standard hard water sample

+ ¾ Test tube of Buffer solution + 4 to 5 drops of EBT indicator.

Indicator : Eriochrome Black T

End Point : Wine Red to Blue.

Pilot Reading : ------ml. to ------- ml.

PART – ( I )

Sr.

No.

Initial B.R.

(ml)

Final

B.R. (ml)

Difference

B.R. (ml)

C B.R.

(ml) X

1

2

3

PART – ( I )

25 ml of standard hard water sample required X ml of 0.01 M EDTA solution [one

of standard hard water = 1 mg CaCO3 ]

Now 1 ml of solution = 1 ppm of CaCO3.

Therefore 1 ml of 0.01 M EDTA = 25 / X=A mg of CaCO3 [Standard Hardness]

Procedure

Observations

Observation

Table

Calculations

PART – ( II ) Estimation of total hardness

1. Pipette out 25 ml of sample hard water solution in a 250 ml conical flask.

2. Add to it 5 to 10 ml of buffer solution and 3 to 4 drops of EBT indicator.

3. Titrate against 0.01 M of EDTA from the burette after shaking it well. End

point will be from red to blue.

This reading say Y ml gives the total hardness of the sample

water.

PART – ( II )

Solution in Burette : 0.01 M EDTA solution.

Solution in Conical Flask : 25 ml of hard water sample

+ ¾ Test tube of Buffer solution + 4 to 5 drops of EBT indicator.

Indicator : Erichrome Black T

End Point : Wine Red to Blue.

Pilot Reading : ------ml. to ------- ml.

PART – ( II )

Sr.

No.

Initial B.R.

(ml)

Final

B.R. (ml)

Difference

B.R. (ml)

C B.R.

(ml) Y

1

2

3

PART – ( II )

25 ml of hard water sample required Y ml of 0.01 M EDTA solution. Therefore

Total hardness in ppm= 25 / X x Y x 1000 / 25 = B mg

Procedure

Observations

Observation

Table

PART – ( III ) Estimation of Permanent Hardness.

1. Pipette out 25 ml of sample hard water in a 250 ml conical flask. Heat the

solution to boiling and continue to boil for about 20 to 25 minutes to convert

temporary hardness causing substances in to insoluble carbonates.

2. Cool and filter off. Reject the residue and collect the titrate for estimation.

3. Add to it 5 to 10 ml of buffer solution and 3 to 4 drops of EBT indicator.

Titrate the solution against 0.01 M of EDTA from the burette.

End point will be from red to blue.

This reading say Z ml gives you the permanent hardness of the

water.

PART – ( III )

Solution in Burette : 0.01 M EDTA solution.

Solution in Conical Flask : 25 ml of hard water sample after

boiled + ¾ Test tube of Buffer solution + 4 to 5 drops of EBT indicator.

Indicator : Erichrome Black T

End Point : Wine Red to Blue.

Pilot Reading : ------ml. to ------- ml.

PART – ( III )

Sr.

No.

Initial B.R.

(ml)

Final

B.R. (ml)

Difference

B.R. (ml)

C B.R.

(ml) Z

1

2

3

Calculations

Result

PART – ( III )

25 ml of hard water sample after boiling required Z ml of 0.01 M EDTA solution.

Therefore Permanent hardness in ppm= 25 / X x Z x 1000 / 25 = C mg

Now Temporary hardness = Total hardness – Permanent hardness

i.e. B – C = D ppm.

1 Total Hardness = B ppm. ………………

2 Permanent Hardness = C ppm. ………………

3 Temporary Hardness = D ppm. ………………