As posted by QX, follow every single instruction carefully.
Chemistry Practical is test your skills on observant and
analysis. If you following the instructions clearly, you will be
able to observe what the question want you to observe. Then from
there, you will be able to analyse the results based on your
knowledge that you have on QA.
Take note on the
1) Observation
2) Know the contents of the chapter on QA, ion test, gas test
etc well.
frequently make mistake wise...
1) Heating - it may seems easy, but students tend to heat not
long enough or too long. The position of the test tube from the
flame is not right either. this is technique mistake.
2) Contamination - Many school's chemistry lab test tubes are
not washed properly. So you'll have residue substances in the test
tube that may affect your test results. If you see unusual
substances in the test tubes, ask for a new set. (the only time
where lab tec wash the test tube properly are for during GCE
exmas)
3) Smells - For a chemistry tutor/teacher, just by smelling,
we'll be able to tell which gas is produced. For you students, you
need to familiarized the different gases.. and try to remember each
of the gases. This one, you may not have many chances.. so grab
every chemistry practical lesson to familiarize yourself with the
gas smell.
4) Colours of substance - sometimes, the best knowledge comes
from experience; and not from the textbook. If you want to do well
for you Chemistry practical, you need to develop this set of
observation skills... If you see a blue crystal, green solid, white
powder, will you be able to at least make a rough guess what is the
crystals/powder are?
5) Litmus testing - It may be very troublesome for some
students, but with enough practice, you can be an expert with the
litmus testing.
6) Time saving tips - Test for CO2.. Usually you'll need the gas
delivery tube connected to Ca(OH)2. For the more experience, we
simply use droppers... to save time.