Xa

2.  Composition of glassware:-
 Laboratory glassware is usually manufactured from
borosilicate glass. It is resistant to the action of
chemicals with the exception of hydrofluoric acid.
 It is made up withstand mechanical breakage and
a sudden change of temp. the main components of
borosilicate glass are:-
 Silica:-80.6%
 Boric oxide:-12.6%
 Sodium oxide:-4.15%
 Aluminium oxide :2.2%

3. Beaker
These have capacities from
5to 5000ml.
They are generally in a
square form , which is
cylindrical and has a
spout.
These are used mainly for
preparation of solutions.

4.  These have capacities of 25-
5000ml.
 These are of different types :
 Conical flask:-
 These are used for performing
titration and for boiling the
solution, since evaporation is
min. because of the conical
shape
.

5.  Flat bottomed flask:-
 These are mainly used for heating liquids.
 Round bottomed flasks:-
 These can withstand higher temp. They may be
heated in a naked flame.
 Volumetric flasks:-
 They are flat bottomed pear shaped vessels with
long narrow necks with a specific vol. mark and
fitted with a stopper. These are mainly used to
make final vol. of the reagent very accurately.

6. Flat bottomed
flask
Round bottomed flasks Volumetric flasks

7. They are available in 10-
2000ml.
They are used to measure
quantity of the liquid. A
high degree of accuracy is
not possible because of
wide bore.

8.  They are available in 25-
5000ml capacities.
 They are cylindrical have
narrow necks and fitted
with stopper made up of
plain glass or amber
colored glass .
 Amber colored bottles are
used to store certain
reagents which are
flammable and light
sensitive .

9.  They are used for measuring
variable quantities of liquid.
They are available in
capacities of 1 to 100 ml.
 They are long graduated
tubes of uniform bore and are
closed at the lower end by
means of glass stopcock.
These are used for titration
and also to dispense
corrosive reagents.

10. These are available in
variety of range for the
separation of:-
Solids from liquids
Liquid from liquids
For pouring liquid ,
chemicals or solutions into
a container
The commonly used
funnels are of diameter of
50, 65,75, and 100 mm.

11.  These are of uniform
thickness & withstand
mechanical & thermal
shocks. Tubes with rim are
preferred when reagent in a
tube is directly heated on the
flame with test tube holder.
 The commonly used test tube
in biochemistry is 15×125
mm

12. These are used for dispensing controlled
quantities of liquids and are classified as:-
Graduated pipettes
 Serological
 Mohar
Volumetric pipettes

13. These are available from
0.1 to 10ml capacities. The
graduation are durable,
resistant to chemical attack
and normal washing.
They are available both in
class A and class B
accuracies. Class A pipettes
are very accurate and used
for quantitative
determination.

14. These are graduated
pipettes marked up to the
tip. These are mainly used
for pipetting reagents .
However 0.1 & 0.2 ml
pipettes are used for
pipetting specimen like
blood ,serum, plasma as
well as different standards.
These are mainly used to
perform serological tests.

15. These are graduated above
the tip so that even if the tip
is broken these can be
used for their full
capacities. The use is the
same as that of serological
pipettes .
These are not convenient
to perform serological test.

16. These pipettes are not
graduated but
designed specifically
with a central bulb to
designed specific
quantity of the
specimen. These
pipettes are more
accurate.

17. These pipettes can be prepared in the
laboratory by using glass tubing. These are
used by attaching rubber teats for the
separation of serum & plasma from the
cells. In qualitative determination , few
drops of specimen are required to perform
a test.