2 Chapter 6 • organising elements Organising elements

6.1
4
Why do we organise elements?
Every day we use materials that have been selected because of their properties. Most
materials are compounds made of different combinations of the 88 naturally occurring
elements chemically bonded together into definite arrangements. Although each of the
elements is different to all the others, there are patterns and trends in their properties.
The periodic table is a way of displaying the elements in a pattern with similar elements
placed near each other. A chemists reads and interprets the periodic table like an
architect reads a plan or a town planner reads a map.
Memory tricks
Have you ever been presented with a large number of
objects, facts or events to remember? How did you go
about it? Teachers experience this challenge every year
when new classes are assigned to them and they need to
remember all your names!
• Work in small groups to test some of your methods.
Groups may choose to work with pictures, words or
objects that they have gathered. Numbers greater than
10 will work best. Methods to consider include the
use of mnemonics, pairing or grouping the items into
smaller, more manageable ‘chunks’ or finding a pattern
that fits the entire set of items.
• Plan and conduct trials for several methods, analysing
and evaluating each to decide on the most effective.
Once complete, consider how this task may be related
to the various systems for naming and/or grouping
things in science.
1 What organising systems have you already
encountered?
2 It has probably been a couple of years since you
studied biological classification, but how did Linnaeus
affect the way scientists classify living things?
3 How may a similar system assist chemists?
Chapter 7 • using chemistry
group 1:
group 2:
light
pinkgroup 3:
garden
Getting elements
organised
The periodic table is a strange shape. It’s not
square or even rectangular, and there’s a gap
across the first couple of rows. Lower down there
are ‘missing’ chunks and two lines of elements are
written below the table, completely detached.
The story of how scientists organised elements
goes back a long way, but the story of the periodic
table itself is relatively short. Scientists have
been trying to get their heads around matter for
thousands of years. Like anything, until a certain
level of understanding is reached, the pieces of
the jigsaw puzzle remain in a bit of chaos. As
soon as some evidence is uncovered, more detail
can be worked out and this can result in the
process of discovery moving much faster.
group 4:
summer
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