When in doubt I check InThinking, the only website that I turn to and I am sure to find a reliable answer. I use it almost everyday during preparation, delivery and assessment phase of any chapter. The best, most reliable resource that one could use...

Mirna Raslan, Wellspring Learning Community, Lebanon

This is an excellent resource for IB chemistry teachers, it is easy to use and navigate your way through.

Sarah Al-Benna, Heidelberg International School, Germany

The InThinking Chemistry website by Geoffrey Neuss is a valuable resource. The presentations are useful and supplement my course textbook by giving students tasks throughout to check their understanding. The topic introductions provide points of interest...

Nick Pinkerton, Tamagawa Academy K-12 & University, Japan

Blogsee all

The danger of prolonged use of proton pump inhibitors

5 July 2019

Students studying the medicinal chemistry option need to be able to explain the three main ways in which excess stomach acid can be controlled... more

104Ku - an anachronism in a gulag

26 June 2019

I was reading an article recently on Dark Tourism which describes a visit in 2017 to Karlag, a former Soviet gulag near Karaganda in Kazakhstan.... more

Subscriber comments

  • Woo, Understanding the difference between one molecule and one mole of molecules (i.e. 6 x 10^23 molecules) is fundamental to understanding chemistry - this is exactly what Qu.4 is testing.
  • Is it a common type of question regarding this topic? I'm confused because this one is quite different from other questions: no use of Avogadro's constant. Thanks.
  • Hi Woo, I think you are confusing molecules and moles. One molecule of CH3COCH3 contains three carbon atoms, six hydrogen atoms and one oxygen atom, i.e. 10 atoms in total.
  • sir . 4. what is the total number of atoms in 3.0 molecules of propanone . i have question to the problem. i wonder why the answer isn't multiply 6*10^24 . the question is how many atoms not mole of atoms . always thanks !!!
  • 20 Sep Geoffrey Neuss
    The nuclear atom answers
    Hi Ivan, Thank you for the kind comments – I’m glad you find the site helpful. The IB is correct when it says mass is not a physical property as you could have 1 g or 100 g of the substance and it is still the same substance. Volume is...
  • 20 Sep Ivan Perez
    The nuclear atom answers
    Dear Geoffrey. First of all, I would like to express my gratitude for all the excellent work you do for the Chemistry of the IB and, therefore, for the dissemination of our subject throughout the world. In addition, myself have been fortunate...
  • 20 Sep Geoffrey Neuss
    Topic 1
    Thank you for sharing Dan.
  • 20 Sep Dan Dubay
    Topic 1
    Hi Geoff and Shalini, I have students take a small piece of dry ice and predict the volume of CO2 that would be produced at SATP. Then we allow it to undergo sublimation and collect the gas in a tube to see how it matches up See here: PS:...
  • 19 Sep Geoffrey Neuss
    Topics 2 & 12
    John, I think It depends upon the question or context in which the electron configuration is being asked or discussed. If the question is ‘What is the full election configuration of argon?’ then the only correct answer is to show each occupied...
  • 19 Sep Geoffrey Neuss
    Alkanes, alkenes & addition polymers
    Hi John, It is a very good question and I’m not sure I’m going to give you a very helpful response as photochemical reactions are quite complex. I think there are several factors here. For gaseous reactions such the chlorination of methane...
  • 18 Sep John Oberthier
    Topics 2 & 12
    Along the same line of [Ar] an acceptable shortened configuration for Ar or would it be [Ne] 3s2 3p6 ? I have seen both, wondering if IB accepts both.
  • 18 Sep John Oberthier
    Alkanes, alkenes & addition polymers
    Hi Geoffrey, I have a question about UV light and bond energy. The Cl-Cl bond energy from the data booklet is 242 kJ. Using E=hv and c=v x lambda. this corresponds to a wavelength of 495 nm which is in the visible range. Similarly, the 193...


Chemistry for the IB Diploma (Oxford IB)

The new edition of the Study Guide (which has sold over 150,000 copies) by Geoffrey Neuss for first exams in 2016.

more info