Working in your Chemistry Laboratory
continued...
Working in your Chemistry Laboratory
continued...
12
13
Using Chemicals
NEVER TASTE A CHEMICAL.
REMEMBER to be careful when carrying
out all the experiments. Wear your Safety
Goggles, but should you get any chemical
in your eyes, get someone else to wash
them immediately with your water bottle
or under a running tap.
You only have a limited supply of
chemicals. Although these can be added to
by buying more from elsewhere, you only
want to work with small quantities.
In the experiments “one measure” is a
level scoopful of the chemical in the round
measuring spoon.
You will add other chemicals to those
supplied and make up “Stock Solutions”
of some of the chemicals that you will need
for many experiments. Keep these in
stoppered containers and bottles. It is most
important that you always label any
chemicals or solutions when you put them
in your own bottles or containers.
TIP:
You will need some empty bottles and
containers. Small bottles that have had
fizzy drinks, or something similar, are
satisfactory, although smaller bottles would
be better - you will need 4. Small plastic
containers that have been used for 35mm
films are perfect for solids. You can get as
many as you want of these for nothing
from your local photo-processor. They will
be pleased to give them to you as they
usually throw them away. NEVER store
chemicals and solutions near or with
foodstuffs.
Using Glassware
If you do have an accident and break some
glassware clean it up immediately. Wipe up
tiny fragments with several pieces of kitchen
roll and throw it away. Wash your hands under
running water when you have cleared up.
One of the trickiest tasks you will have to do is
to push the glass tubing into a cork. It is very,
very easy to break the tubing and cut your
hand when doing this so take great care.
TIP: A Hand Sprayer.
A small (1 pint) garden or indoor plant
sprayer that is readily available at Garden
Centres and DIY stores is ideal. It has a
trigger action and is designed to give a
spray. By rotating the spray head a fine
jet of water can be produced instead.
This is very controllable by lightly
squeezing the trigger. Additionally the
sprayer has the advantage of being easy
to refill by just unscrewing the water
container.
Using Filter Papers
You will use the filter papers supplied to
separate solids from liquids and for the
Paper Chromatography experiments. Always
use a new paper for each experiment. You
may need more papers than supplied here.
Very cheap filter papers can be cut from
Coffee Filter Papers; get the white ones
rather than the brown ones if you can. You
are advised to use the small filter papers and
Coffee Filter Papers for filtering and retain
the large filter papers supplied here for the
Chromatography experiments. Filter papers
are folded as shown in the diagram below.
TIP:
Thoroughly wet the cork and the end
of the tubing with a strong solution of
washing-up detergent. Hold the glass
tubing and the cork in a tea-towel, or other
cloth and push the tubing gently with slight
twisting into the cork.
Wash the excess detergent off the cork
and tubing and allow them to dry. Once it
is in the cork it is usually impossible to
remove the tubing without breaking it
unless you cut the cork. Don’t try.
