IB Chemistry Subject Guide

Summary of the Curriculum Changes

It is obvious that education has been disrupted all over the world with the precedented COVID-19 pandemic in 2020. IB aims to continue supporting schools in educating students to compassionate, life-long learners under these very challenging times. IB staff have been working closely with the school leaders, examiners and educators from all the countries to keep the quality, validity and reliability of the Diploma Program. IB is committed to fairness and equality to all students in their 2021 examination periods regardless of the current situation. Therefore, with the recognition of the impact of COVID-19 outbreak, IB has announced a range of adaptations in the assessment components of 28 exams to address the disruptions. Some components for some subjects are removed while some others are amended to allow teachers more time and flexibility to create a suitable context for the needs of students' conceptual understanding and making links with other disciplines.

Below are the adaptations made in the marks allocated to each paper and Internal Assessment (IA) and their updated weighting in Chemistry and other Group 4 Sciences. Important: Visit the official IBO page for the most updated information about this subject.

About The Exam Content

2021 Examination Adaptations

Standard Level (SL)

Higher Level (HL)

IMPORTANT: Paper 3 is removed from 2021, 2022 examination periods to reduce the content. Teachers will have more time to design their teaching and learning environment around the needs of their students and prepare them for the examination period. The decision about Paper 3 for 2023 onwards will be announced by IB later.

In chemistry SL and HL, students study the same topics but with different depths. By analysing the data in the following table, it can be understood which topics are allocated more time and where IB wants students to focus.

Another important information that can be interpreted from the table is how different the HL content be in some topics. In some topics like Acids and Bases, core is limited to general understanding of acid and bases and pH calculations whereas the HL content is expanded to understanding of the acid base titration processes, buffer systems and salt hydrolysis.

IB tends to ask questions from all subjects in SL and HL of Paper 1 but for paper 2 there are some topics which students get a significant amount of questions every year. Those are stoichiometric relationships; there is always a question to find the number of atoms or molecules of a complex chemical compound or the coefficient of a molecules in a balancing equation. The HL group may get electrochemistry related parts, asking, oxidation states/numbers or a redox titration.

Another popular topic in Paper 2 is organic chemistry, both groups get a full question on organic compounds. This question would include Structural isomers in SL and Geometrical isomers for HL students. HL students always get a few reaction-mechanism questions since they learn about Nucleophilic Substitution reactions and reactions of Benzene. Electrophilic substitution is only covered with Benzene molecule. If SL students were to get a reaction mechanism, it would mostly be on homolytic fission reactions.

Hess's Law in energetics drawing Lewis structures, Calculation of Bond enthalpies from a given chemical equation are among the common questions.

Students in both groups should expect questions from measurement and data analysis where students are most of time asked to identify an unknown organic compound by analysing their Mass, IR and HNMR spectra.

Tips: Before The Exam

Experienced IB teachers believe that, 25% of achieving a good grade in IB depends on how effectively students do their reviews before the exams after all the content is covered.

Get used to using the data booklet

Chemistry has a very long, 40+ page data booklet. It is not easy to find the correct information in the exam unless one knows where to look clearly. Avoid waste of time.

Familiarise with the IB question formats

Many students make a mistake in their first attempt because they don't understand the question properly.

Do timed tests when you feel confident enough

Time puts extra pressure on students, which in return brings simple mistakes and loss of points.

Revise on all the topics and go over the mistakes you made

Go over the mistakes by reviewing those concepts from study guides or textbooks.

Tips: During The Exam

Use time wisely, do not spend too much time on one question.

In Paper 2, questions are given in long paragraphs which may seem very complicated at the beginning.

Divide the question into smaller chunks that is understandable

Write chemical formula, chemical equations for stoichiometric relationship when relevant

Look for the key terms, and hidden information that will help them to solve the problem

Show the working steps

DO NOT forget to present the result with the correct units and significant figures