Mixing of two solutions.
55
Class IX
EXPERIMENT No: 9
AIM: To study the external features of root, stem, leaf and flower of monocot and dicot plants.
Material Required :
Plants of Hibiscus/Peturnia/rose/pea and grass/maize/bamboo/lily or, any other ornamental
herb with flower and fruits, simple or dissecting microscope, hand lens, slide, coverslip and razor
/blade.
Procedure :
1.
Observe the differences in the external features of stem, leaf, root, flowers and seeds.
2.
To study the leaf, see their shape and venation i.e. parallel or reticulate.
3.
To study the roots, wash them properly and then spread on the paper and study their
nature i.e. tap root or fibrous.
56
4.
To study the flower, count the number of sepals & petals in the flower is trimerous or
pentamerous.
5.
Remove the seed coat and count the number of cotyledons is mono cotyledon or
dicotyledon.
6.
Take a transverse section of ovary and count the number of carpels ie bicarpillary or
tricarpellary.
57
Observations :
Observe the important features that distinguish a monoct and a dicot plant and list the
features of difference between than in the table given below.
S. No.
Feature
Monocot
1.
Leaf venation: (Parallel/Reticulate)
2.
Leaf shape : (broad/narrow)
3.
Roots : Fibrous/ tap root
4.
Floral parts : multiple of 3 or 5
5.
Sepal : number and colour
6.
Petals : number and colour
7.
Pistil : number of carpels
8.
Cotyledon : one or two
Dicot
Inference :
The monocot plants can be differentiated from dicot plants by the presence of parallel
venation in leaf, narrow leaves, fibrous roots, floral parts in the multiple of 3 and one cotyledon in
their seeds.
Precautions :
1.
A hand lens must be used to see the leaf venation or number of cotyledons.
2.
Small / Tiny plants must be selected for study.
3.
The plants bearing plowers and/or seed must be used tor studying.
58
Class IX
EXPERIMENT No: 10
AIM: To study the life cycle of mosquito.
Materials Required :
Charts showing the life cycle of a mosquito and/or museum specimen of stages in the life
cycle. Permanent slides and compound microscope.
Procedure :
1.
Observe the preserved specimen and name the stages.
2.
Observe the chart carefully and note the different stages in the life cycle.
3.
Discuss the characterstics of each stage.
Observations :
Eggs : Deposited in water, they hatches in water.
Larva : Lives on the surface of water, moults several time.
Pupa : A stage just prior to the adult stage, pupae do not feed.
Adult : It emerges from pupae body parts harden and starts flying.
Precautions :
1.
The chart should clearly indicate the life stages of mosquito.
2.
The hand lens should be used to see the different stages of specimen.
59
Class X
EXPERIMENT No: 1
AIM: To find pH of the following samples using pH paper
a.
Dil. Hcl
b.
Dil. solution of NaOH
c.
Dil. solution of acetic acid
d.
Lemon juice
e.
Tap water
f.
Dil. solution of Na2 CO3
Materials Required :
All above solution samples, tap water, pH paper with standard colour chart, dropper and white
tile.
Procedure :
1.
Take above mentioned samples separately and clean test tubes labelled as
(a) to (f) respectively.
3.
Take separate strip of pH paper and place it on a clean and dry white glazed tile corers
pending to each sample.
4.
Compare the colour produced on pH paper with the standard colour chart & record the
corresponding value of pH.
Observations :
Sample
a
Dil. Hcl
b
NaOH
C
Acetic Acid
d
Lemon Juice
e
Tap Water
f
Na2 CO3
pH
60
Inference :
a.
When pH is 7, neutral
b.
When pH is above 7, sample is basic
c.
When pH is below 7, smaple is acidic
We find that HCl, Acetic acid and lemon juice are acidic while NaO2 and Na2 Co3 are basic
in nature Tap water is ....................
Precautions :
1.
pH paper should not be touched with wet hand or dirty hand.
2.
Separate dropper should be used for each sample.
3.
Use colour chart given with the corresponding pack of pH paper.
(Don’t use colour chart of any other packet.
61
Class X
EXPERIMENT No: 2
AIM: (a) To study the properties of on acid it’s reaction with
(i) Litmus (ii) Zine (iii) Na2 Co3
(b) To study the properties of a base NaOH by it’s reaction with
(i) Litmus (ii) Zine (iii) Hcl
Part (a)
Materials Required : Hydrochloric acid, blue Litmus solution, Zinc granules, Na2 Co3 dropper and
test tubes.
Observation Table :
Experiment
Observation
Inference
1.
Take 1 ml dil. HCl
in a test tube and add a
few drops of blue litmus
solution.
Solution turns red
HCl has acidic nature
2.
Take some zinc granules in a
test tube and 1 ml of dil.
HCl to it.
Bubbles of H2 gas are
given out
HCl reacts with Zn to
form H2 gas
Brick effervesence is
produced due to the
HCl and Na2 CO3 react
to give CO2 gas
3. a. Take 1 ml dil. HCl in a test
and add a pinch of solid
b.
Na2 CO3 to it.
founation of CO2 gas
Pass the gas through
freshly prepared lime
water
Lime water turns milky.
Resykt : Hydrochloric acid
i.
Shows acidic nature
ii. turn blue Litmus red
iii. reacts with zinc to give hydrogen gas
iv. reacts with Na2 CO3 to give CO2 gas.
Precautions : Use clean test tube for litmus test part (b) Materials Required :
Dil. Hcl, NaOH solutions (aq.), Test tubes, red litmus solution, zinc granules and dropper etc.
62
Observation Table :
Experiment
Observation
Inference
1.
Take 1 ml NaOH (aq.) in a
test tube and add a few drops
of red litmus solution.
Solution turns blue
NaOH is basic in nature.
2.
Take 2 ml NaOH (aq.) in a
clean test tube and add
2 pieces of Zn granule to it.
Bubbles of H2 gas are
given out.
Zn reacts with NaOH
solution to give H2 gas
3.
Take 3 ml Na OH (aq.) in a
clean test tube and two
drops of phenolphalein
solution to it.
Pink coloration is
produced
NaOH is a base
4.
Add dil. Hcl to
above solution drop
by drop
Solution be comes
colourless
HCl nentralizes NaOH
Inference : Sodium hydroxide
i.
show basic nature
ii. turns red litmus blue
iii. reacts with Zn to give H2 gas
iv. is neutralized by HCl
Precaution :
1.
Use NaOH carefully. It is corossive
2.
Use clean test tube for phenolphthalein test or litmus test.
63
Class X
EXPERIMENT No: 3
AIM: To perform and observe the following reactions and classify them into :
1.
i.
Combination reaction.
ii.
Decompositions reactions.
iii.
Displacement reaction.
iv.
Double displacement reaction.
1.
Action of water on quick lime.
2.
Action of heat on ferrous sulphate.
3.
Iron nails kept in copper sulphate solution.
4.
Reaction between sodium sulphate and barium chloride solution.
Action of water on quick lime
Materials Required : Quick lime, distilled water beaker, test tubes, filtrations set, red litmus paper.
Procedure : Perform the action of water on quick lime according to the following table :
Experiment
Observation
Inference
1.
Take 40 ml of water in a
beaker and add 4 g of quick
lime to it. Stir it with glass rod.
Brisk effervescence
begins.
A new substance in
formed,
2.
Touch outer surface of the
beaker
It is hot
Heat in evolved
during the reaction.
3.
Place a drop of liquid of
liquid of beaker on a red
litmus paper.
It turns blue
New substance formed
in pasic in nature
4.
Take about 10 ml filtered
liquid from the above beaker
and blow air from mother.
It turns milky
New substance formed
is slaked lime
Result :
1.
Water and quick lime directly combine to from calcium by hydroxide along with li
beration of heat.
2.
The reaction is :
(i)
Combination reaction
64
(ii)
Exothermic reaction
Precautions :
\2.
1.
Quick lime should not be touched with hands.
2.
Add quick lime very carefully to avoid spurting of the mixture.
Action of heat on ferrous sulphate :
Materials Required : Ferrous sulphate crystals (Solid), Acidified potassium dichromates
solution, blue litmus paper, test tubes, test tube holder.
Procedure :
Experiment
Observation
Inference
1.
2 g of solid ferrous sulphate
is taken in a clean dry test
tube and heat it.
A colorless gas forms
leaving a brown yellow
solid in test tube.
Ferrous sulphate
decompose on heating
2.
Smell the gas carefully.
It smells like burning
sulphur.
The gases are oxides
of sulphur.
3.
Bring a moist blue litmus
paper near the mouth of
test tube.
It turns to red.
Oxides of sulphur are
acidic in nature.
Result :
1.
Ferrous sulphate on heating decomposes and produce ferric acids & oxides of ferrous.
2.
The type of reaction in thermal Decomposition reaction.
Precautions :
3.
1.
The test tube should well cleaned & dry.
2.
Smell the gas carefully.
3.
Mouth of test tube should be kept away from you while neating.
Iron nail is kept in Copper Sulphate Solution :
Materials required : Copper sulphate solution, iron nails, test tube, thread, stand.
Procedure :
1.
Experiment
Observation
Inference
Add 2 g copper sulphate in
20 ml of water in a test tube
and place 2 iron nails.
After few minutes a brown
coating forms on iron nail.
Copper is displaced by
iron from its solution.
65
2.
Compare the colour of
iron nail and solutions
before & after the
experiment is done.
Iron nail colour turns
brown where as the
solution turns light
green.
Iron is more reactive
them copper.
Result :
1.
Iron being more reactive, it displaces copper form the solution.
2.
The type of reaction is displacement reaction..
Precautions :
1.
Iron nail should be cleaned before dipping in solution.
2.
Reaction between sodium sulphate and barium chloride.
Materials required : Solid sodium sulphate, barium chloride, distilled water, conical black, test
tubes.
Procedure :
Experiment
Observation
Inference
1.
Take 10 ml solution of
sodium sulphate in a test
tube and 10 ml solution
of barium chloride in another
test Tube. Mix together in a
beaker.
A white precipitate is
observed immediately.
White precipitate is
barium sulphate.
2.
The conical precipitate is
left undisturbed for some
time.
It settles down in the bottom
of flosk.
Barium sulphate is
insoluble in water.
Ruesult :
1.
On mixing the solution of sodium sulphate and barium chloride a white precipitate is
obtained.
2.
The type solutions reaction is Double displacement reaction.
Precautions :
1.
The solutions should be prepared in distilled water.
2.
Use the chemicals in small quantity.
66
Class X
EXPERIMENT No: 4
AIM: a. To observe action of Zn, Fe, Cu and Al metals on the following salt solutions (aq.)
1.
Zn So4
2.
Fe So4
3.
Cu So4
4.
Al2 (SO4)3
b.
To arrange Zn, Fe, Cu and Al metals in the decreasing order of reactivity.
Materials Required : Test Tubes, Test tube stands, Beaker, small pieces of metals- Cu, Al, Zn and
Fe. Saturated aq. Solution of Zn So4, FeSO4, CuSO4 and Al2 (SO4)3.
Procedure :
1.
Take 10 ml aq. Solution of Al2(SO4)3, FeSO4 and CuSO4 in 3 test tubes separately. Add 2
small pieces of Zn granules in each.
2.
Take 10 ml of aq. Solution of Al2 (SO4)3, ZnSO4 and FeSO4 in 3 test tubes separately. Add
2 pieces of copper in each.
3.
Take 10 ml of aq. Solution of ZnSO4 FeSO4 and CuSO4 in 3 test tubes separately. Add 2
small pieces of Al in each.
4.
Take 10 ml of aq. solution of Al2 (SO4)3, ZnSO4 and CuSO4 in 3 test tubes separately. Add
2 small pieces of Fe in each.
Observation for Zinc metal :
Solution
Al2(SO4)3
FeSO4
CuSO4
Observation
No Reaction
Fe is
displaced
Cu is displaced
Observation for Copper metal :
Solution
Al2(SO4)3
ZnSO4
FeSO4
Observation
No reaction
No Reaction
No Reaction
Solution
ZnSO4
FeSO4
CiSO4
Observation
Zn is displaced
Fe is displaced
Cu is dispalced
Observation for Al metal :
67
Observation for Fe metal :
Solution
ZnSO4
CuSO4
Al2(SO4)3
Observation
No reaction
Cu is
No reaction.
Result : On the basis of above expt. Reactivity of given metals is Al > Zn > Fe > Cu
Precautions :
1.
Test tubes should be cleaned properly before taking any solution.
2.
Test tubes should be labelled properly to identify the solution taken in the respective test
tube.
68
Class X
EXPERIMENT No: 5
AIM: To study the dependence of potential difference (v) across a resistor on the current (i), and
determine its resistance. Also plot a graph between v and i.
APPARATUS/ MATERIALS REQUIRED : 4 dry cells ( 1.5 V each ) or a battery eliminator, copper
wires with bare ends, one way key, an ammeter, a voltmeter, a rheostat, a resistor ( approximately
5 ohm ), sand paper
69
PROCEDURE:
1.
Rub the ends of the connecting wires with sand paper, so that the shining copper metal is
seen.
2.
Remove the plug from the one way key, K.
3.
Connect the key, the rheostat, the ammeter, the voltmeter, cells or battery eliminator and
the resistor as shown in the diagram.
4.
Insert the plug key and check the deflection in the ammeter and voltmeter.
5.
Adjust the slider of the rheostat in such a manner that the current passing through the
resistor is small ( about 0.1 A ).
6.
Read the value of the potential difference from the voltmeter.
7.
Record the value of current and potential difference and take out the plug key.
8.
Repeat the experiment 5 to 6 times for different values of current in ammeter and record
the potential difference from the voltmeter.
OBSERVATION:
Least count of ammeter =……….
Least count of voltmeter =……….
S. No.
Current (A)
Potential difference (V)
Resistance
R= V / I in ohm
1
2
3
4
5
6
Mean Resistance = (R1 + R2 + R3 + R4 + R5 + R6) / 6 = …….. ohm
Plot the graph between (V) and (I) by taking I on the x axis and V on the y axis. Join the points. The
graph obtained is a straight line.
RESULT:
1.
The resistance of the conductor is the ratio of the potential difference and the
current.
70
2.
The graph is a straight line suggesting V is directly proportional to I. This verifies the
ohm's law.
3.
The slope of the graph V / I is the magnitude of the resistance.
PRECAUTIONS:
1.
Clean the ends of the connecting wires by sand paper.
2.
Connections should be tight.
3.
The plug key should be inserted only when you are ready to record the reading.
4.
Remove the plug key when you have finished your reading.
5.
Keep the value of current in the circuit as low as possible.
6.
Zero errors of the voltmeter and ammeter should be taken into account and adjusted
accordingly.
71
Class X
EXPERIMENT No: 6
AIM: To determine the equivalent resistance of two resistors connected in series.
APPARATUS / MATERIALS REQUIRED: 4 dry cells ( 1.5 V each ) or a battery eliminator, copper
wires with bare ends, one way key, an ammeter, a voltmeter, a rheostat, two known resistors
( approximately 1 to 5 ohm ), sand paper
72
PROCEDURE:
1.
Rub the ends of the connecting wires with sand paper, so that the shining copper metal is
seen
2.
Remove the plug from the one way key, K.
3.
Connect the key, the rheostat, the ammeter, the voltmeter, cells or battery eliminator and
the two resistors in series as shown in the diagram.
4.
Insert the plug key and check the deflection in the ammeter and voltmeter.
5.
Adjust the slider of the rheostat in such a manner that the current passing through the
resistors is small.
6.
Read the value of the potential difference from the voltmeter.
7.
Record the value of current and potential difference and take out the plug key.
8.
Repeat the experiment 5 to 6 times for different values of current in ammeter and record
the potential difference from the voltmeter.
OBSERVATION:
Least count of ammeter =……….
Least count of voltmeter =……….
S. No.
Current (A)
Potential difference (V)
Resistance
R= V / I in ohm
1
2
3
4
5
6
Mean Resistance = (R1 + R2 + R3 + R4 + R5 + R6) / 6 = …….. ohm
RESULT: The mean resistance of the resistors is equal to the sum total of the individual
resistances of the resistors and is according to the formula Rs = R1 +R2
PRECAUTIONS:
1.
Clean the ends of the connecting wires by sand paper.
73
2.
Connections should be tight.
3.
The plug key should be inserted only when you are ready to record the reading.
4.
Remove the plug key when you have finished your reading.
5.
Keep the value of current in the circuit as low as possible.
6.
Zero errors of the voltmeter and ammeter should be taken into account and adjusted
accordingly.
74
Class X
EXPERIMENT No: 7
AIM: To determine the equivalent resistance of two resistances when connected in parallel.
APPARATUS / MATERIALS REQUIRED: 4 dry cells ( 1.5 V each ) or a battery eliminator, copper
wires with bare ends, one way key, an ammeter, a voltmeter, a rheostat, two known resistors
( approximately 1 to 5 ohm ), sand paper.
75
PROCEDURE:
1.
Rub the ends of the connecting wires with sand paper, so that the shining copper metal is
seen.
2.
Remove the plug from the one way key, K.
3.
Connect the key, the rheostat, the ammeter, the voltmeter, cells or battery eliminator and
the two resistors in parallel as shown in the diagram.
4.
Insert the plug key and check the deflection in the ammeter and voltmeter.
5.
Adjust the slider of the rheostat in such a manner that the current passing through the
resistors is small
6.
Read the value of the potential difference from the voltmeter.
7.
Record the value of current and potential difference and take out the plug key.
8.
Repeat the experiment 5 to 6 times for different values of current in ammeter and record
the potential difference from the voltmeter.
OBSERVATION:
Least count of ammeter =……….
Least count of voltmeter =……….
S. No.
Current (A)
Potential difference (V)
Resistance
R= V / I in ohm
1
2
3
4
5
6
Mean Resistance = (R1 + R2 + R3 + R4 + R5 + R6) / 6 = …….. ohm
RESULT: The mean resistance of the resistances in parallel is less than the individual resistors
and is according to the formula Rp = R1R2 / (R1+R2)
PRECAUTIONS:
1.
Clean the ends of the connecting wires by sand paper.
76
2.
Connections should be tight.
3.
The plug key should be inserted only when you are ready to record the reading.
4.
Remove the plug key when you have finished your reading.
5.
Keep the value of current in the circuit as low as possible.
6.
Zero errors of the voltmeter and ammeter should be taken into account and adjusted
accordingly.
76
Class X
EXPERIMENT No: 8
AIM: To prepare a temporary mount of a leaf peel to show stomata.
MATERIAL REQUIRED: Fresh leaves of a plant such as Petunia, Dianthus or Lily, watch
glass,slide,cover slip,brush,a piece of blotting paper, razor blade ,safranin,glycerine,compound
microscope.
PROCEDURE:
1.
Remove a peel from the lower surface of the leaf as it has more stomata as compared to
the upper surface of leaf. This can be done by carefully pulling out a thin peel with the
help of a razor/blade.
2.
Immediately put the leaf peel in water in watch glass.
3.
Now add a few drops of safranin stain to the watch glass to stain the leaf peel.
4.
Cut a small piece of leaf peel.
5.
On a slide put a drop of glycerin in the centre. Now place this leaf peel on the slide.
6.
Gently place the cover slip.
7.
Remove the excess stain and glycerin with the help of the blotting paper.
8.
Now observe the stomata under the compound microscope under low power. (10X)
OBSERVATION:
Observe the stomata under the microscope field. The shape of Guard cell, the number of
chloroplasts in the guard cells should be observed.
77
Inference:
A stoma is a pore, found in the leaf and stem epidermis that is used for gaseous exchange.
The pore is bordered by a pair of specialized cells known as guard cells that are responsible for
regulating the size of the opening. The term stomata is also used collectively to refer to an entire
stomatal complex, both the pore itself and its accompanying guard cells.The guard cell are
responsible for opening of stoma. These have a number of chloroplasts. When the guard cells are
shrunk the stoma closes!
Precautions:
1.
Do not use excess stain while preparing the slide.
2.
Mount the peel in the centre of slide.
3.
Avoid air bubbles while putting the cover slip.
4.
Adjust the microscope properly to see the stomata.
78
Class X
EXPERIMENT No: 9
AIM: To show experimentally that light is necessary for photosynthesis.
Materials Required :
Potted plant, black paper strip, test tube, alcohol/ethanol, water petri dish, iodine solution.
Procedure :
1.
Keep potted plant in dark for about two days.
2.
Fix black paper stip on a leaf as shown in the figure.
3.
Put the plant in sunlight for about eight hours.
4.
Pluck leaf, remove black paper strip.
5.
Boil the leaf in alcohol/ethanol using water bath.
6.
Wash this leaf in hot water to make it soft.
7.
Place leaf in petri dish and pour 2 or 3 iodine drops.
Light is necessary for Photosynthesis
Observations :
1.
During boiling, green leaf looses colour and become pale yellow.
2.
Water treatment to leaf makes it soft.
3.
After iodine treatment leaf portion not covered by black paper stip changed to dark blue
colour.
79
4.
Black paper covered area does not show positive result to starch iodine test.
Inference :
1.
Black paper strip does not allow light to fall on covered portion.
2.
Photosynthesis takes place in the area exposed to light.
3.
Photosynthesis does not take place in black paper strip covered portion.
4.
It indicates that light is necessary for photosynthesis.
Precautions :
1.
Potted plant should be completely destarched in the beginning.
2.
Black paper strip should not allow light to enter covered leaf area.
3.
Always use water bath to boil leaf in alcohol/ethanol.
80