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Chemistry AS Level, Posters, Harris Academy
Mr Glen Akibo-Betts
Text 1, the poster about the development in the understanding of the atomic structure.
I think this piece really needs a timeline, just to show the development from, as the
statement here, ‘too small for the eyes to see.’ Well, that was Greek, and it would
have been nice to known that was Greek. And I would have appreciated all the
different key scientists, scientific discoveries or scientists that made the discoveries,
to have had dates next to the timeline, so the really thing for me, . . . . . . that would
have made it outstanding would have been a timeline, this flow of our understanding
of the atomic structure.
Secondly, the images. They’re images that are linked to the Plum Pudding Model,
and to Rutherford’s gold foil experiment, that need labels or need a description.
There’s a description in the text, however, it doesn’t explain the importance of the
difference that happened when we went from the Plum Pudding Model to the Gold
Foil Model. For example, the fact that in the Rutherford Gold Foil Model, that the
centre became the positively charged core, and that’s not here. And the idea that he
knew it was a positive-charged core because when we fired other particles, which are
also positive, at it, we saw a deflection. And that addition to this would have made it
stand out.
Text 2, again, again, chose the modern development of the structure of the atom. I
really like this, it starts with Democritus, with the 400 BC statement that ‘matter’s
made up of small particles, I will call them ATOMA!’ Brilliant. And the next big
jump was 1804, with Dalton thinking about matter consisting of tiny balls, which
again was the atom idea but with more evidence to back it up. The Plum Pudding
Model diagram is labelled, so, it explains what we thought was happening with
Thompson’s Plum Pudding Model in terms of the electrons embedded in a plum
pudding of positive charge.
It goes right through to Rutherford’s experiment, Niels Bohr’s idea of quantum
mechanics. And, finally, something that I don’t know about, which was really
interesting for me, which means that, as a specialist, I want to now go and find out
what the Bee Hive Theory is. What it also does is, for the non-specialist, it gives
them a really good grasp of 400 BC to present day what’s happening. One other thing
I think could have made this really, really, really good was the idea that the
Rutherford experiment was an image linked to that, that has not been labelled or
explained in enough detail, the idea that we then discover that there’s a core in the
centre of the atom which is positively charged, and we found that by having alpha
particles deflected from them. So, all-in-all, I really liked this poster.
Text 3, which is not the structure of the atom but the development of the Periodic
Table of Elements. So, a similar sort of timeline style task for the student to research.
It started off really well with the idea that 1978, de Lavoisier, put together a group of
33 elements on their reactivities, and this is the origins of the Periodic Table, a
classification of elements based on their properties. And it goes through the triads
idea by Dobereiner, and in the middle, the Mendeleev idea of the Periodic Table,
which was really important, which was almost the first idea that the Periodic Table
could be organised by atomic mass as opposed to chemical properties or reactivities
and so on.
Then, it moves on to other discoveries, in 1913, that you could also describe the
Periodic Table in terms of atomic mass and atomic number. And, finally, to the idea
that we’re still - looking at the Periodic Table, looking at the transient relevance – to
this day, trying to synthesise new and ever more complex elements. I really like this,
but I thought the use of images could have been slightly better. We’ve got the current
Periodic Table in here. What I thought could have made this really outstanding was,
for me, the first categorising of elements, by de Lavoisier, 33 elements, how were
they grouped? And why were they grouped as such? And then maybe another image
of Mendeleev’s Periodic Table, which was ever so important in terms of our grouping
them purely by reactivity into grouping them by atomic mass. And then finally to our
current Periodic Table and looking at the progression. So, although there’s a timeline,
it would have been really nice to have seen a graphical development, as well.