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SCIENCE LABORATORY
SUBMITTEDBY
SARANYA.M.V
(NATURAL SCIENCE)
SUBMITTEDTO
Mrs. SUSHAMA PRABHA
(LECTURE IN NATURAL SCIENCE)
SUBMITTEDON
25-07-2015

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INDEX
Sl.No Content Page No.
1 Introduction 3
2 Significance and its Organization 4
3 Importance of Laboratory work 4
4
Selection and Purchase of Apparatus, Chemicals and
Equipments
6
5 Maintenance of the Laboratory 6-7
6 Laboratory Rules 7-9
7 Accidents in the Laboratory and first aid 9-10
8 Precautions while doing Laboratory Practical’s 10
9 Registers in the Laboratory 10
10 Suggestions to develop Infrastructure of a Laboratory 12
11. Conclusion 13
12 Reference 14

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INTRODUCTION
Science laboratories have been part of high school education for two centuries, yet
a clear articulation of their role in student learning of science remains elusive. This report
evaluates the evidence about the role of laboratories in helping students attain science learning
goals and discusses factors that currently limit science learning in high school laboratories.
One of the important functions of the science laboratory is the deepening of the
students’ understanding that scientific concepts and application are closely related to his own
natural environment. Practical work in science even at the school stage is essential because of
the fact that we ‘learn by doing’. Scientific principles and applications are thus rendered more
meaningful. Moreover it is a fact that an object handled impresses itself firmly on the mind than
an object merely seen from a distance or in an illustration. Most children like doing things with
their hand. Practical work provides an activity which can be profitable and emotionally
satisfying.

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SIGNIFICANCE AND ITS ORGANISATION
One of the important functions of the science laboratory is the deepening of the students’
understanding that scientific concepts and application are closely related to his own natural
environment. Practical work in science even at the school stage is essential because of the fact
that we ‘learn by doing’. Scientific principles and applications are thus rendered more
meaningful. Moreover it is a fact that an object handled impresses itself firmly on the mind than
an object merely seen from a distance or in an illustration. Most children like doing things with
their hand. Practical work provides an activity which can be profitable and emotionally
satisfying.
i) Importance of Laboratory work
1. The achievement of modern science are mainly due to the application of experimental
method. It is in the laboratory that pupils get a training in this important phase of science
study.
2. In doing laboratory work the pupils get a chance for activity both physical and
intellectual and they are learning by doing.
3. Laboratory exercises train them in scientific thinking they develop scientific attitude and
scientific methods as a result of laboratory work.
4. The laboratory helps the pupils in the development of manipulative skills.
5. The experiments done serve as a source of motivation. They are interested in handling
materials and doing experiments.
6. The laboratory, the teacher comes into closer contact with the individual and helps them
to bring out of their difficulties.
General Principles of Laboratory Construction
1. The laboratory should be compact in arrangement but at the same time capable of
expansion to meet the growing needs of the school.
2. Fittings and furniture should be planned to be convenient for use and economical in the
long run.
3. The arrangements of furniture should ensure ease of supervision and proper lighting.
4. There should be enough storage accommodation and sufficient wall space should be left
for additional fixtures.

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Laboratory Rooms
It may be a combined class-room and laboratory for both physics and chemistry. The
science room should preferably in the east-west direction to avoid direct sunlight getting into
rooms. Sufficient clear space on the south to reflect sunlight for experiments in light. The
laboratory rooms should be well lighted and ventilated so that light should preferably enter from
the left. This may be supplemented from light from above or behind. The total wall space taken
up by doors and windows should be above ¼th of the floor space. The ventilators should be
below one foot of the ceiling. Physics laboratory should be preferably on the ground floor
where there would be least vibrations. Chemical laboratory to be so situated that gases and
vapours do not affect the rest of the building.
Rooms to have high wall (about 15 ft), large sized, windows in pairs, opposite to each
other. Floor to be perfectly smooth in cement without dirt lodging corners but with a slight
slope to help cleaning. Doors and windows should open outwards.
1. Furniture and Fittings: Working benches where students have to work should be placed
in rows parallel to the demonstration table preferably between windows. They should be
provided with shelves without drawers. The top should perfectly be made smooth and
given paraffin glazing. The height of each bench may be about 3ft.
2. Demonstration Table Dimension: The table can be used for demonstration as well as
for placing common articles to be used by all students during practical experiments. The
top plane may be given a paraffin coating.
3. Sink: To be fitted in the walls
4. Black Board - 7’x4’: It might be cemented area of wall treated with black paint.
5. Almirah.
6. Bottle shelves.
7. Book shelves (to be placed near the entrance or exit doors).
8. Blow pipe
9. Waste Boxes.
10.A fume cupboard.
11.Wall shelves for reagent bottles.
12.Drawing racks near the sinks.

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ii) Selection and Purchase of Apparatus, chemicals and Equipments
The list of apparatus and chemicals to be purchased must be prepared with the
details of the experiment to be performed by the pupils and demonstrated by the teacher.
It is better to buy a few additional articles to guard against breakages. The number of
units of costly apparatus may be reduced and pupils may be allowed to work in
combination.
The list of apparatus may be divided into two.
(1)Essentials and
(2)Desirables.
In preparing the list due consideration should be paid to all parts of the subject. The
teacher may not be tempted by the attractive descriptions and catalogues. When the essentials
have been purchased, the teacher might think of getting down desirables.
After finalizing the list, the teacher or Head Master will invite quotations from science
firms. It is always best to deal with firms that supply the best available materials. The teacher
can also visit the factories or show rooms of the dealers to get a correct idea of the nature of
supply. If possible the teacher might select the apparatus himself and get them pack in his
presence so as to avoid the trouble of sending back unsuitable materials.
In ordering goods, full specifications of the articles required should be given. For
example, the quality and capacity of beakers, flasks & retorts the diameters and heights of
troughs, gas jars, and dishes. Wires whether bear or insulated, cages of the wires – are not
given, the teacher is likely to receive things never expected as or ordered.
One or two large purchases a year is preferable. Raw materials like timber, metallic sheet,
rods, wires, and tools may be bought to best advantages from local leaders. Particular care must

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be exercised in the choice of glass ware. They should be mechanically strong and resistant to
chemical action as well as extreme changes of temperature.
Specimen Sheet of the Purchase of Apparatus and Chemicals
Sl.No.
Date of
Purchase
Name of firm/
company
Articles
Ordered
Articles Received
With Voucher No.
Cost of each
Articles Remarks
iii) Maintenance of the Laboratory
No laboratory work can be considered complete without an equipment for making simple
apparatus and executing minor repairs. Hence there should be a small workshop with proper
fittings for wood work and metal work. These equipments enable the laboratory work to be
done without interruption and also allows many improvement to be carried out in the form of
different apparatus. Since it is the labour and direction that cause more than the materials
employed. It is economical in the long run if we have a laboratory workshop. Also there is an
additional advantage of getting an elementary training to the pupils who have a mechanical
aptitude.
In a laboratory workshop, there should be small carpenters, bench and tools for wood
work. There should also be metal working tools, hammers, players, drill press and a small vice
and anvil. A blow pipe table fitted with glass lamps and bellows for glass work should be used.
By way of raw materials there should be wooden planks, strips, nails, wires, screw, sheet, metal,
glass, rubber tubing, corks, rubber stoppers it.
Planning Laboratory Work
It very often happens that laboratory work is not properly correlated with class teaching
or everyday experience of the pupils. So the pupils my go through the experiments according to
laboratory directions quite mechanically. Very few pupils want to know the facts and principles
to be made clear from experiments.
In order to get the whole – hearted purposeful activity of the pupils, laboratory work
should be organized as unavoidable and integral parts of regular instruction. A careful
consideration of the relations between the scientists and their laboratory work will indicate the
true relation between the pupil and the laboratory. Just as the scientist works in his laboratory to
find out certain facts and relations to solve a problem the pupil must also make use the
laboratory to find out first hand observation and experiments to solve problems. Hence the main
function of laboratory work should be to enable the pupils to solve significant problems.

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The problem can be formulated during class room discussion and it may be solved with
the help of laboratory work. When so planned laboratory work becomes a vital part of science
programme and the problems chosen must arise from the pupil’s daily experiences and that
might be different in different localities. So the teacher must plan his science course in detail to
include several significant laboratory problems.
iv) Laboratory Rules
(Steps to maintain discipline in laboratory)
Rules are important because the laboratory happens to be a place of potential dangers.
The Science teacher is the supreme authority in the laboratory and he should be strictly obeyed.
Discipline is taught by making the pupils know what to do in the laboratory rather than don’ts.
The laboratory is essentially a workshop without any sort of confusion.
1. No pupil should be allowed to enter the laboratory in the absence of the teacher or
laboratory assistant.
2. Every pupil may have a seat assigned to him
3. The arrangement in the laboratory should be such that there is no need to move a pupil
from his seat.
4. Everyone should pick up the practice of putting up his hand to call the attention of the
teacher.
5. When the pupils are working in groups they might be allowed to discuss a low tone.
6. Unnecessary talking should be strictly forbidden.
7. While they are doing experiments, the pupils must examine the apparatus given and
report defects if any.
8. Reagent bottles should be returned to the shelves immediately after use.
9. Stoppers are also to be replaced on the bottles.
10. Waste papers, burnt match sticks should not be thrown into the sink. Waste boxes should
be used.
11. Scribbling figures on furniture and on loose sheets of paper should never be permitted.
12. The teacher can get the help of the pupils to distribute apparatus and materials to clean
them after use and to replace them at the end.
13. The pupils must be insisted on keeping the furniture neat and clean and arranging the
apparatus neatly on the bench during the experiments. After use the apparatus must be
left clean.
14. The large number of appliances and materials in the laboratory is a source of temptation
to the mischievous pupils. Hence the teacher has to be very vigilant. They are to be given
tight work and particularly watched by the teacher.
15. Bottles must be labeled clearly.

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16. The wall of the laboratory can be decorated with pictures of scientists and diagrams of
apparatus.
17. Useless substances/ broken glass, chemicals, solid waste must be deposited in a separate
basket.
18. A bucket full of water must be kept not only when experiments are being done but
always.
Economyin the Laboratory
1. Money should be spent for purchasing only those things used in laboratory or classroom.
2. Only good type of apparatus especially of glass should be bought.
3. Pupils should not damage apparatus through ignorance or carelessness. Delicate
apparatus like the balance, burette, thermometer should be handled with care.
4. Only the minimum amount of chemicals needed to produce the desired result should be
used. It should be advantageous of the teacher and the pupils to have some idea of the
prices of things. Wasteful habits should be discouraged even with cheap materials. As a
rule, the cheapest material having the necessary effect should be made use of. Whenever
commercial variety is enough other should not be used. In the preparation of Cl2, NaCl is
preferred in practical instead of KCl.
5. Use of large sized apparatus like big flasks must be avoided. The modern techniques of
microchemistry are also helpful to the teacher in minimizing the consumption of
chemicals.
6. Use of homemade apparatus (improvised apparatus) helps in keeping down the cost of
running down a laboratory.
7. Costly apparatus like the barometer and balance require special attention. All apparatus
and furniture should be maintained in good condition.
Take care while handling
 Glasses, acids, strong alkalies
 Gases like H2S, SO2, Cl2 and CO.
 Inflammable materials like Petrol, Alcohol, CS2
 Salts of lead, mercury and zinc.
 Explosive materials
v) Accidents in the laboratory and first aid
Accidents may happen in the laboratory. So it is necessary to keep First Aid Kit.

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 This should contain acetic acid, bandages, carbolic acid, cotton, dressing guaze,
eyedropper, forceps, glycerine, milk of magnesia, plaster, plucker, scissors, sodium
carbonate, tincture iodine, Vaseline.
 It would be better to display a chart depicting the accidents that are usual in the
laboratory and remedies.
1. Wounds: Apply cotton dipped in tincture iodine.
2. Burns from fire: Cover the portion with lined dipped in Vaseline.
3. Burns from acids: Wash with plenty of water and then with 1% sodium
bicarbonate solution.
4. Burns from alkalies: Wash with plenty of water and then with weak vineager or
lime juice.
5. Burns from phosphorous: Wash with plenty of water and then cover with cotton
dipped in silver nitrate.
6. Injuries to eye: It should be dealt with by doctor.
7. Acid in the eye: The eye should be opened and closed under water. It should be
washed with 1% solution of sodium bicarbonate.
8. Alkali in eye: The eye should be thoroughly washed with water and then with a
solution of 1% of boric acid.
9. Electric shocks: Switch of the electrical supply. Beat with a wooden stick. Admit
to a hospital.
vi) Precautions while doing Laboratory Practicals
1. Laboratory glass ware must be never used as drinking vessels.
2. Solutions split on the bench or floor should be cleaned up immediately.
3. Concentrated solutions should be diluted before they are poured down the sink.
4. Do not point to the other people with a test tube.
5. Do not look into the mouth of a test tube while heating its contents.
6. Do not sniff at toxic materials.
7. For constant boiling, chips of marble pieces should be placed in the liquid under boil.
8. Always use test tube holders while heating materials in a test tube.
vii) Registers in the Laboratory
Once the apparatus is received, the articles should be properly checked and entered in
the stock register the same time. The type of registers in each educational institution are:
1. Permanent Stock register: It contains details of articles which are not liable to be
consumed or broken like magnets, iron stands, wooden blocks, Newton’s color disc.
Some articles like ammeter, stop watches, thermometer, voltmeter are also entered in the

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register as they are considered nonconsumable. Working and non working models, charts,
telescopes and microscopes can be entered in this register.
Specimen of Permanent Stock Register of Articles
Stock Register…………………….Department
Name of the Articles purchased
Sl.No.
Month &
Date Particulars
Details of
Company rate
Number of
breakable articles
Number of
hand
Teacher’s
Signature
1. Breakable Stock Register: It includes the articles of glassware, flasks, test tubes, beakers,
pipettes, burettes and funnels.
Specimen of Breakable Stock Register
Sl.No Month&
Date
Particulars of
the company
bill no.
Receipt Consumed/
Written off
Balance
Teacher
incharge
Value as on
31-3-200
Qty Rate Amt. Qty Amt Amount
Rs. Ps.
2. Consumable Stock Register: It includes chemicals and other fluids liable to be
consumed such as acids, alcohol, distilled water, potassium permanganate and the like.
Sl.No. Month&
Date
Details of
Broken
materials
Reason for
breakage
Signature of student Signature of
Science teacher
Signature of
Head of the
Dept.
3. Order Register: It includes the record of the orders sent for the purchase of new
apparatus.
Specimen of Order register
Sl.No Month&
Date
Particulars Receipt Consumable
item details
Balance
Signature
Of the
Teacher
Remarks
Qty Rate Amt. Date Qty
It is better if the Photostatorder of copy be stapled on the left hand page and the copy the
voucher on the right hand of the register.

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4. Requirement Register: The most appropriate method of collecting suggestions for new
resources for the science staff, is to note the ideas in a requirement register. The
suggestion should be arranged according to priorities.
Sl.No. Name of Items Quality Size Quantity Teacher’s
Signature
Remarks
1
2
3
4
Beaker
Conical flask
Test tube
Acids
Borosil
Borosil
Borosil
Concentrated
250ml
500ml
6”x¾”
Bottle of 1 litre
3 dozens
2 dozens
6 dozens
2 Gallons
Uses of Stock Register
1. The science teacher should number all the pages of every stock register.
2. The teacher should divide the stock register into a number of subtopics as Dynamics,
Electronics, Heat, Information Technology, Mechanics, Optics and the like.
3. All entries should be made alphabetically.
4. Leave the first few pages of the register for index.
5. Spacing should be given between entries so that additional items can be entered at
proper place.
6. Broken and consumed items should be entered in the column provided in the stock
register and make it upto- date.
7. Stock register should be initialed by the concerned teacher and counter signed by the
head of the department at the end of each month.
viii) Suggestions to develop Infrastructure of a Laboratory
1. Find sources of fund.
2. Space for laboratory.
3. Enough apparatus and chemicals and they are to stored properly.

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CONCLUSION
This report evaluates the evidence about the role of laboratories in helping students attain
science learning goals and discusses factors that currently limit science learning in high
school laboratories. The laboratory helps the pupils in the development of manipulative
skills. Laboratory exercises train them in scientific thinking they develop scientific
attitude and scientific methods as a result of laboratory work. The experiments done serve
as a source of motivation. They are interested in handling materials and doing
experiments.

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REFERENCE
 Science Education – Theoretical Bases of Teaching and Pedagogic Analysis
- Dr. T.K.Mathew
- Dr. T.M. Mollykutty
 www.lab-aids.com

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