Transcript IGCSE Coursework - DAVIS-DAIS

October 2010
IGCSE Coursework
Assessment criteria for IGCSE practical assessments
The skills assessed are C1 to C4.
C1: Using and organising techniques, apparatus and
materials
C2: Observing, measuring and recording
C3: Handling experimental observations and data.
C4: Planning, carrying out and evaluating investigations
Each skill is assessed on a six point scale. Level
six is the highest level of achievement.
Notice that although the scale has six points
descriptions are only given for 2, 4 and 6. A
grade in between may be given if the work falls
between two levels.
C1: Using and organising techniques,
apparatus and materials
2- Simple one stage instructions for an experiment can be followed. If
many instructions for an experiment are given some of it can be
followed but help may be given to complete the task. The instructions
may be written, oral or from a diagram. The apparatus and materials
are used properly however some reminders may be given on safety.
4- Can follow the instructions for an experiment with many stages
without help. The apparatus is used properly with no reminders on
safety.
6- Can follow the instructions for an experiment with many stages
without help and can modify or adjust one step in order to complete
the task. The adjustment must be taken as a result of the previous
instructions. The apparatus is used properly with no reminders on
safety.
C2: Observing, measuring and recording
2- Can make observations or take readings in an experiment when help
is given. The data obtained can be recorded in a table when the table is
provided in a full form including headings and units.
4-Can make observations and readings in an experiment with only a
brief outline of what is expected. The observations can be made
without help but accuracy may be lacking. The results can be recorded
in a table when the headings only are given.
6- Makes good observations and measurements that are accurate. For
example readings repeated, good detail included etc. The results are
recorded accurately in a table and no help is given in the set up of the
table.
C3: Handling experimental observations and
data.
2- The results in an experiment are processed e.g. calculations carried
out, graphs plotted but detailed help is needed or if no help is given the
results are incompletely processed. A simple conclusion is drawn from
the experiment.
4- The results in an experiment are processed and only very brief and
partial help is given. e.g. the student is told the axis to use in the graph.
The graph may be plotted without help but there are some inaccuracies.
A conclusion is drawn from the experiment which is consistent with the
results. The patterns in the results are noted.
6- The results are processed correctly without any assistance.
Anomalous results are noticed and commented upon. The sources of
experimental error are noted and commented upon. The conclusions
are written in a way that recognises trends and relationships.
C4: Planning, carrying out and evaluating
investigations
2 – An experiment is planned and carried out but the variables may not
be fully controlled or measured. The method is adjusted but with no
real direction.
4-An experiment with more than one stage is planned and carried out.
Most of the variables will be controlled or measured. The original plan
is commented upon critically and changes may be carried out in the
method that is relevant and positive.
6- A logical experimental plan is produced and carried out. In the
experiment there will be more than one variable to be controlled or
measured. The procedure is fully evaluated and improvements are
suggested. The method may be modified during the experimental work
and this is fully justified. Unexpected results are dealt with e.g. left out
of a line of best fit etc.
IGCSE CHEMISTRY COURSEWORK
Investigating the evaporation of aftershave
Skills assessed
C1: Using & organizing techniques, apparatus and materials
C2: Observing, measuring & recording
C3: Interpreting & evaluating experimental observations and data
Aftershave lotions are used to cool the skin after shaving. You
are going to make your own aftershave and compare it with
some commercial aftershaves. In the experiment you are
going to investigate which aftershave produces the greatest
cooling effect.
1. Make your own aftershave lotion to test. You need to mix
together 8cm3 of alcohol, 1cm3 of glycerol and 4cm3 of water
in a boiling tube. Stopper the tube and shake to mix the
ingredients properly.
2. Attach a small amount of cotton wool to a thermometer bulb
using a rubber band.
3. Record the temperature reading on the thermometer
4. Now dip the cotton wool covered end of the thermometer into
one of the lotions.
5. Remove the thermometer and place the wet end on a white
tile.
6. Record the temperature at regular intervals for a suitable
time period. You will need enough results to plot a graph for
each lotion investigated.
7. Repeat with each of the lotions provided you can also try
water as a comparison. Try to make your tests as fair as
possible.