I have compiled frequently asked paper 2 questions in IB chemistry SL from 2016 to 2021 past papers with markschemes and possible questions. In chemistry, each paper 2 question has specific words/phrases and points to earn full marks. Knowing these points will significantly improve your grades as these questions are recurring and you are likely to encounter them in real IB exams, or certainly in your school exams.


[Table of contents]


[Sample excerpts]


This textbook is designed to help you understand how each mark is awarded in Paper 2 questions. Most of the answer forms are directly extracted from the actual Markscheme from 2016–2021 papers. Some are, however, made up to simulate expected questions and answer schemes. Also, it is paramount you do not forget there are a number of possible questions that were never asked before, including but not limited to, definitions, calculations, listing examples, and safety/environmental concerns.


Chapter 1: Stoichiometric Relations

(a) Outline why a real gas differs from ideal behavior at low temperature and high pressure. [1]

✓ Finite volume of particles {requires adjustment to volume of gas}


Short-range attractive forces {overcomes low kinetic energy}

(b) Suggest why many chemicals, including hydrogen peroxide, are kept in brown bottles

instead of clear colorless bottles. [1]

✓ Decomposes in light

 “sensitive to light” is accepted


Chapter 2: Atomic Structure

2.1 The nuclear atom

(a) Describe how the relative atomic mass of a sample of an atom could be determined from its mass spectrum. [2]

✓  Multiply relative intensity by {m/z} value of isotope


Find the frequency of each isotope

✓  Sum of the values of products/multiplication {from each isotope}


Find/calculate the weighted average

 [1 max] is awarded for stating “m/z values of isotopes AND relative abindance/intensity” but not stating that they need to be multiplied.



  • Total number of pages: 31 pages
  • Topic: IB Chemistry SL Paper 2 Model answers from past papers and expected questions
  • Subject: Chemistry
  • The file is in PDF format.