Updates for 2023

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There are a few updated guides I have uploaded. The changes are only very minor and sometimes just formatting issues.

Good luck with the summer examinations.

Summer examinations 2022

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All the exam boards have published advanced notice of the major topics that will be covered in this years exams. These are meant to provide some help in preparing for the exams. I think the help that these give at A-level Chemistry is questionable. If you choose not to revise certain topics that are not on the major topics list, you could end up with a lower grade.

The key part of the guidance used is this phrase: “Topics not included on the list may still appear in multiple-choice items, questions with a low tariff, or via synopticity.” So any topic could appear on a multiple choice or as a minor part of a question on another topic. The difference in number of marks between a major topic and a low tariff topic is not specified- so potentially there could be anything up to 5 or 6 marks on a topic not listed. For example, with AQA, NMR does not feature on the major topics listed, but it is easy to add an NMR question worth a couple of marks onto almost any organic question- so you can be sure NMR will appear somewhere. Even if the major topics make up 80% of the marks, you cannot afford to throw away 20% of the marks if you want a high grade.

In addition, Chemistry is a subject that makes most sense when you have revised everything and make the connections between topics. If you take short cuts in your revision, you will be less able to answer the synoptic questions that range across topics.

So in conclusion, if you want a high grade and have a university place dependent on it, then my advice is revise everything to the same degree.

Chemistry summer reading (updated)

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This is an update on a previously written blog post about some wider reading for Chemistry. I have added on several new books written in the last few years. The newer books are highlighted in bold. It is good to see a bumper selection of new chemistry popular science books. Some of these are a little harder to categorise as they take a broad sweep of chemistry, history and social issues.

Now that the chemistry exams are over and the long summer stretches ahead why not grab a chemistry book to deepen your knowledge a bit and find out something interesting. I don’t mean read a chemistry A-level text book but something a little different. Chemistry does not seem to get the same range of popular science books that Biology and Physics do, but there are some great books out there. The list contains books I know are in my school library but hopefully people not at Bancroft’s will find some of these books in your local/school/college library. Some of these books are no longer in print although they mostly have been published in the last ten years, so hopefully are not that hard to track down.

Books about Elements.

  • The Elements- a visual exploration of every know atom in the universe: Theodore Gray 2009
  • The Elements- the new guide to the building blocks of our universe: Jack Challoner 2014
  • The elements- a very short introduction: Philip Ball 2004
  • The Periodic Table: A Very Short Introduction: Eric Scerri 2011
  • Nature’s Building blocks An A to Z guide to the Elements: J Emsley 2011
  • The Periodic Table: A Field Guide to the Elements: Paul Parsons 2013
  • Elements of Murder – A history of poison: J Emsley, 2006
  • Periodic Tales: The Curious lives of Elements: Hugh Aldersey-Williams  2012
  • The Periodic Table: A visual guide to the elements:  Tom Jackson 2017
  • Seven Elements That Have Changed The World: Iron, Carbon, Gold, Silver, Uranium, Titanium, Silicon   John Browne   2014
  • The Disappearing Spoon…and other true tales from the Periodic Table Paperback – 28 Jul 2011   by Sam Kean 

 

The first two in this elements list are big glossy ‘coffee table’ books with lots of oversized pictures and rather less text. They are undeniably attractive though. You will find a lot more text and interesting information in the Emsley and Parson books. Maybe get one with pictures and one with more text and then you get the best of both worlds.

You will find John Emsley appear several times on the list. He is a great writer of popular chemistry books. He writes about every day and unusual chemicals and mixes science with history and good stories. They are always great books that are easy to dip into. The Elements of Murder book just deals with a few highly poisonous elements used for dastardly purposes. If you can find ‘The shocking History of Phosphorus’ by him, do get it. It is a really interesting book about the element with arguably the most interesting history. It is unfortunately no longer in print and I don’t have it my school library.

‘Periodic  tales :The Curious lives of Elements’, ‘The disappearing spoon’  and ‘Seven elements that have changed the earth ’ are a;; newer books that combine the chemistry with a broader sweep of the related history and politics  and have lots of interesting stories.

 

Books about Molecules

  • Molecules : Peter Atkins 2003
  • Molecules at an exhibition: J Emsley, 1999
  • Vanity, Vitality and Virility- the science behind the products you love to buy: J Emsley 2004
  • Healthy, Wealthy, Sustainable World; J Emsley, 2010
  • H2O – a biography of water; Philip Ball ,2000
  • Oxygen- the molecule that made the world; Nick Lane 2003
  • Molecules: The Elements and the Architecture of Everything:  Nick Mann, Theodore Gray 2014
  • Why Does Asparagus Make Your Wee Smell?: And 57 other curious food and drink questions:    Andy Brunning  2016
  • Stuff matters : the strange stories of the marvellous materials that shape our man-made world : Mark Miodownik. 2014

These are books about interesting and common molecules. Again these are mostly popular science books that are easy to dip into. The ‘Molecules’ book by Atkins and ‘Stuff Matters’ are on the recommended reading list for Cambridge University Natural Sciences.

Stuff matters is more a materials science book but a great read with lots of chemistry.

General Chemistry readers

  • Chemistry: A Very Short Introduction; Peter Atkins 2015
  • Physical Chemistry: A Very Short Introduction; Peter Atkins 2014
  • Reactions: The private life of atoms ; Peter Atkins  2013
  • What is Chemistry? ; Peter Atkins 2013
  • The joy of chemistry- The amazing science of Familiar things; Cobb, Fetterolf 2010
  • The Atom: The building block of everything ; Jack Challoner  2018 
  • Reactions: An Illustrated Exploration of Elements, Molecules, and Change in the Universe ; Theodore Gray  2017
  • 50 Chemistry Ideas You Really Need to Know ;  Hayley Birch   2015  
  • Strange Chemistry: The Stories Your Chemistry Teacher Wouldn’t Tell You ; Steven Farmer 2017 
  • Elemental: How the Periodic Table Can Now Explain (Nearly) Everything : Tim James 2018

This list includes several books by Peter Atkins who is another prolific writer of both popular and academic chemistry books. The book ‘What is Chemistry?’ is quite short but is excellent. Well worth a read. It really gets to the most important features of the subject, and is more than accessible to an A-level student.

History of chemistry Books

  • Mendeleyev’s dream: the quest for elements; P Strathern 2001
  • The big bang – A history of explosives; GI Brown, 1998
  • The Periodic Table. Its story and its significance; EF Scerri- a detailed exploration of the development of the periodic table 2006
  • A tale of 7 elements. Eric Scerri 2013
  • Curious Tales from Chemistry: The Last Alchemist in Paris and Other Episodes  Lars Öhrström  2015

These are books more about the history of the subject than the chemistry but obviously the chemistry features. The ‘Mendeleyev’s dream’ book is actually more about whole history of chemistry rather than just Mendeleyev. ‘The Periodic Table. Its story and its significance’ is an excellent history of the development of the Periodic Table.  I seem to remember it argues that Mendeleyev’s work was based in many other scientists work rather than him being a lone visionary he is sometimes made out to be. Eric Scerri’s book ‘A tale of 7 elements’ is about the search for the seven missing elements such as Hafnium, Francium and Technetium that were 7 gaps in the late 19th century periodic table.

More advanced science Readers

  • Why chemical reactions happen: James Keeler, Peter Worthers 2003
  • Made to Measure: New Materials for the 21st Century by Philip Ball 1999
  • Chemical Structure and Reactivity: Keeler and Worthers: a degree level book
  • Chemistry³: Introducing inorganic, organic and physical chemistry:  first year undergraduate book

These books are definitely not popular science books for a little light reading. The first two books are on the reading list for pre- Natural Sciences at Cambridge. If you are thinking about applying to do Natural sciences at Cambridge (on the physical side) then you ought to read ‘Why chemical reactions happen’. It is an excellent book that that really does explain why reactions happen. It is not an easy book though as it goes beyond A-level and introduces the ideas of Atomic and Molecular orbitals. Bright A-level students will cope though. It is important to read it from the start and read it all through. Don’t write it on your UCAS personal statement if you have not read it though. One of my ex-pupils who had read it was interviewed by Peter Worthers at his Cambridge interview and there were questions. (He got in!)

Language of rates of reaction

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This applies to both A-level and GCSE. It is amazing how many marks are thrown away when writing about the collision theory.

Increasing temperature, concentration and surface area all increase the frequency of collisions. 

It is not enough to say only there are more collisions as there is no reference to time.

More collisions per second is fine though.

A greater chance of collisions is not good enough as probability is not the same as frequency (This is sometimes accepted though.)

 

When talking about increased concentration then say there are more particles per unit volume.  

More particles on its own is not good enough.

 

When talking about temperature the particles have more energy and move faster. They therefore collide more frequently. More particles will also collide with more energy than the activation energy. Leading to more successful collisions.

Be careful with activation energy. Sometimes candidates write particles have more activation energy. This is not correct though.

Activation energy  is the minimum energy needed for the collision to be successful. Particles can’t have more or less activation energy.  Particles can only have more or less energy than the activation energy. ( just two missing words completely changes the meaning)

If the particles have less energy than the activation energy they bounce off each other and do not react. If the particles have more energy than the activation energy then they react.

Language of bonding

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The golden rule in writing about bonding is to be clear about what particles are attracted to each other and what that attraction is.

Do not use the words atoms, ions, and molecules carelessly. A wrongly chosen word can throw away all your marks.

If a question is asking about the high melting point of magnesium oxide, a student will not get much credit for just saying it has strong bonds or strong ionic bonds.

A good answer might be: MgO has a giant lattice structure with strong electrostatic forces of attraction between oppositely charged ions. These require a lot of energy to break.

Similarly if talking about hydrogen bonding in ethanol it is essential to make to make it clear that you know  it exists between  ethanol molecules.

Statements like ethanol has hydrogen bonding, or contains hydrogen bonds are too vague, and potentially hint at a misunderstanding. Some students mistakenly believe the hydrogen bond in ethanol is the actual O-H covalent bond within the molecule. Any confusion with covalent bonds will result in losing all the marks in the question.

A good way of phrasing it is that ethanol forms hydrogen bonds between  molecules.