PRACTICAL - I
INTRODUCTION: Familiarity of apparatus, equipments
Used in the Chemistry lab
Chemistry laboratory work shop to learn skill, technique and important concepts of
chemistry. Before conducting any experiment, students should be familiar with
commonly used apparatus.
Test tube: It is a hollow cylindrical thin glass tube with one end closed.
Beaker: Flat bottomed cylindrical vessel of different capacities such as 100,150, 200 ml.
It is made up of glass.
Boiling tube: It is similar to that of test tube but it is made of hard glass.
Funnel: It is a cone shaped glass of different diameter with a narrow mouth at
thebottom i.e. is long. It is used for filtering.
Conical flask: It is a glass vessel with conical shape with a narrow mouth. It
is used for titration.
Burette: It is a graduated cylindrical tube. There is a nozzle and a stop cork at
the end of tube used for titrations.
Measuring flask: It is used in quantitative analysis to prepare a solution of a
particular volume. The flask of different capacities 50,100,200,etc.
are used.
Glass rod: Used for mixing solution for dissolving solid in a liquid.
Pipette: It is a long tube with a bulb in the middle. It is used to measure fixed
volume of solution. It is narrow at the ends.
China Dish: It is made up of porcelain used for evaporation, crystallization etc.
Tripod stand: It is used as a support to keep China dish or beaker.
Wire gauze: It is a square piece of thin wire mesh with soft asbestos coating
in the middle. It is placed on a tripod stand for the safe heating of
the glass vessel.
Other familiar apparatus used in the chemistry lab are as follows:
* Watch glass
* Wash bottle
* Water bath
* Funnel stand etc.
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1
PRACTICAL - II
BUNSEN BURNER AND TYPES OF FLAME
Bunsen burner is a common device used for heating purpose in laboratory. Gases such as
Hydrocarbons are used to get the flame.
Different parts of a Bunsen burner:
1. Base : It is made up of cast iron base connecting of:
2. Gas-inlet: used for connecting gas pipe.
3. Nipple : It is made up of brass with a fine hole for gas outlet from the burnertube.
4. Airregulator : Used to control air supply at base as in diagram.
5. Burner tube : It is a long tube made up of brass with two air holes at the lower
end. It is secured onto the nipple.
WORKING:
The rubber tube is connected to the gas tap Ignite the gas at the top of theburner tube gas supply
is controlled by the nob. By controlling the gas supplyand adjusting air hole a fine light blue flame
is observed.
The flame consists of following zones.
1) Dark zone – near the base of pipe
2) Luminous zone – At the middle of the flame. It contains partially burnt gas.
3) Non-luminous zone – Outermost zone. The tip is the hottest part of outer most zone. In this
zone
complete combustion takes
place.
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2
PRACTICAL – III
TO STUDY THE PROPERTY OF AN ACID(dil. HCl)
AND AN ALKALI (dil. NaOH)
APPARATUS REQUIRED: Test tube (2 in number), Test tube holder.
CHEMICALS:Dil. Hydrochloric acid, Dil. NaOH solution, litmus papers
(blue and red), Magnesium strip, Copper metal, sodium
Carbonate and distilled water.
THEORY:
1) Acid turns blue litmus paper top red.
2) Alkali turns red litmus paper to blue.
2) Magnesium strip reacts with dilute acid to liberate hydrogen gas but NaOH does
not react.
Mg + 2HCl
MgCl2 + H2‘
(s)
(aq)
(aq) (g)
3) Dil acid reacts with sodium carbonate to liberate carbon dioxide gas with effaervenses.
Na2CO3 + 2 HCl2NaCl + H2O + CO2
(s)(aq)
(aq) (li) (g)
TEST
OBSERVATION
1) i) Take 2ml of dil. HCl in a test Blue litmus turns red.
tube. Add a piece of blue litmus
paper
No change is observed.
ii) To the acid taken in a tarts
tube. red paper
2)
Take 2ml dil. NaOH in a test
tube.
i) Add red litmus paper
Red litmus changes to blue.
No change.
ii) Add blue litmus solution
3)
INFERENCE
HCl is acidic in nature.
Acid – no change in red litmus
NaOH is basic in nature.
Alkali –no change in blue litmus
3) i) Add magnesium metal
strip to dilute HCl.
Mg reacts with HCl to liberate Acids react with metals to liberate
H2 gas.
hydrogen gas.
ii) Add dilute NaOH
NaOH does not react.
Bases do not react with metals.
Acid reacts with Na2CO3 to
liberate CO2 (on passing
through lime water it turns
milky)
The acid reacts with Na2CO3 to
liberate CO2
4) Take sodium carbonate
(Na2CO3) in a test tube A
and B.
i) Add dilute HCl to A.
ii) Repeat the test by adding dil. NaOH does not react.
NaOH to B
Bases do not react with Na2CO3 to
form CO2
NOTE:
1. Do not handle the chemicals bare hands (use spatula)
2. Acids and bases should be handled with care. It may cause burns.
3. Small amount of chemicals should be used for correct result.
4. Do not inhale gases
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4
PRACTICAL - IV
TO STUDY THE REACTION OF METAL
WITH DIFFERENT SALTS SOLUTIONS
To observe the action of Zn, Fe, Cu and Al metals on salt solution.
i)ZnSO4ii)FeSO4 iii) CuSO4iv) Al2(SO4)3
THEORY: Displacement reaction
More active metal displaces less active metals from salt solution.
APPARATUS REQUIRED: Test tube (4 in Nos) labelled as A, B, C and D.
CHEMICALS:Solutions of i) ZnSO4 ii) FeSO4 iii) CuSO4iv)Al2(SO4)3
PROCEDURE:
1)Keep 4 test tubes with a mark A, B, C and D
2)Add about 5 ml of aqueous solution of
ZnSO4 – Colourless
FeSO4 – light green
CuSO4– light blue
Al2(SO4)3 – colourless
in four test tubes A,B,C and D respectively.
1)Add a small strip of Zn to all the test tubes A,B,C and D, and observe for about
5 minutes.
2) Repeat the experiment with other metals like Fe, Cu and Al metal.
(NOTE: The metal strip should be cleaned with sand paper)
OBSERVATION
METAL
ZnSO4
Al2(SO4)3
FeSO4
CuSO4
Zn
No change
No reaction
Displacement (green to Displacement (blue to
colourless)
colourless)
Fe
No reaction
No reaction
No change
Cu
Al
No reaction
Displacement
No reaction
No change
No reaction
No change
Displacement (green to Displacement (blue to
colourless)
colourless)
REMARK: Decreasing order of reactivity
Aluminium > Zinc > Iron > Copper
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Displacement (blue to
light green)
5
PRACTICAL - V
EXPERIMENT TO SHOW THE PROCESS OF NEUTRALIZATION
THEORY : ACID – BASE REACTION
An acid reacts with base to form salt and water. When dil Hydrochloric
acid is added to Dil. NaOH. The H+ of acid reacts with OH¯ on of a base to
form water.
HCl + NaOH
NaCl + H2O
(aq)(aq)
(aq) (li)
+
[H + OH¯
H2O]
This process is known as neutralization reaction.
APPARATUS:2beakers 100 cc, glass rod, and droppers.
CHEMICALS: Dil. solution of hydrochloric acid and sodium hydroxide solution
of almost the same concentration.
PROCEDURE:
The beakers containing the solutions are labelled A and B. Beaker Acontains Dil. Hydrochloric acid
and beaker B contains dil. Sodium hydroxidesolution.
Keep beaker (B) containing 10ml dil. NaOH on a porcelain plate. And 2-3drops of phenolphthalein.
The solution turns to pink colour. With the helpof dropper add Dil. Hydrochloric acid, drop by
drop with constant stirring,till pink colour becomes light pink. Solution B changes to light pink a
justcolourless. This indicates that the mixture has become neutral. Also observe that the reaction
is exothermic and heat is liberated
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