Download Functional Groups Help Sheet

WJEC GCE Applied Science – Unit 5: Forensic Science
Portfolio Activity 5a(i) – Functional Groups
In this portfolio activity, which forms part of the assessment for this
Unit (Report a(i) : ‘Identification of Organic Chemicals’), you need
to find out about four families of organic chemicals and how they
are related.
You need to know about ALKANES, the simplest of the organic
chemicals and then you can choose four to study from the
following list:






Alkenes
Haloalkanes
Carboxylic acids
Aldehydes and Ketones (Carbonyl Compounds)
Alcohols (including Phenol)
Esters
You may want to consult your teacher before you choose your compounds.
You will need to show that you are able to compare the structure and properties of
the compounds that you choose with the alkane that it is originally based on. You
can do this by:
Defining what an alkane is (structure and chemical and physical properties)
and then choosing a particular one on which to base your comparison.
Say what makes each chemical group structurally different from the alkane on
which it is based (called the parent alkane).
Say how the different structure affects the properties (chemical and physical)
of the chemical group compared to the parent alkane.
Getting Started
1) First build a model of an alkane, eg ethane – see Starter Sheet for how to
make the molecule.
2) Build a model of the compound from your first chemical group. See what
makes it different to the alkane and write this down.
3) Build models for the other four groups you have chosen, writing down how
each is different to the parent alkane.
Next Steps
Now you can go onto looking for information on each of the groups of compounds –
starting off with alkanes and then looking at your chosen compounds. You need to
state what happens to the alkanes as the length of the carbon chain is increased.
Remember that you only need to compare the structures and physical and chemical
properties of the compounds. There are some good ‘A’ level Chemistry websites on
the Internet or you could look in Chemistry textbooks.
Recording Information
Record the information in any way you feel appropriate – part of your assessment
will be to present information clearly and logically.
Assessment
Objective
Criteria
(a) Knowledge
&
Understanding
AO1
(b)
Terminology &
Conventions
(c) Information
&
Presentation
Possible
examples
of unit
content (if
applicable)
Level of Response
Low
Candidates should:
High
Candidates should:
demonstrate basic
knowledge and
understanding of the
science. There may be
significant omissions
2 marks
demonstrate good
knowledge and
understanding of the
science with few
omissions
4 marks
use basic scientific
terminology and
conventions in some of
their work
2 marks
select information and
present it clearly,
occasionally using the
appropriate form such as
extended prose, tables,
diagrams etc and/or
accurate spelling,
punctuation and
grammar.
1 marks
use correct scientific
terminology and
conventions in most of
their work
4 marks
select relevant
information and present it
clearly and logically,
usually in an appropriate
form such as extended
prose, tables, diagrams
etc and/or accurate
spelling, punctuation and
grammar.
2 marks
Candidates should:
demonstrate detailed
knowledge and
understanding of the
science with no significant
omissions from most parts
of the specification
6 marks
use scientific terminology
and conventions
accurately in all their work
6 marks
select relevant information,
present it clearly and
logically, using the
appropriate form such as
extended prose, tables,
diagrams etc with accurate
spelling, punctuation and
grammar; and then evaluate
and justify it.
3 marks
NB - These criteria will also be applied to the practical aspects of this report.
Candidate
mark
Assessment
Objective
You will be assessed on the following criteria: