IB Chemistry Subject Guide:
Curriculum Revisions & Exam Tips
“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.”
Author: Dr Ayse Yavuz UlkerIB Chemistry Examiner and IA moderator, IB and AP Chemistry teacher
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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.
Chemistry Standard Level (SL)
PAPER 1
Marks for May 2021: 30
(Current Weighting: 20%)
Modified Weighting for May 2021: 30%
PAPER 2
Marks for May 2021: 50
(Current Weighting: 40%)
Modified Weighting for May 2021: 50%
PAPER 3
Marks for May 2021: REMOVED
(Current Weighting: 20%)
Modified Weighting for May 2021: N/A
IA
Marks for May 2021: 24
(Current Weighting: 20%)
Modified Weighting for May 2021: 20%
Chemistry Higher Level (HL)
PAPER 1
Marks for May 2021: 40
(Current Weighting: 20%)
Modified Weighting for May 2021: 30%
PAPER 2
Marks for May 2021: 90
(Current Weighting: 36%)
Modified Weighting for May 2021: 50%
PAPER 3
Marks for May 2021: REMOVED
(Current Weighting: 24%)
Modified Weighting for May 2021: N/A
IA
Marks for May 2021: 24
(Current Weighting: 20%)
Modified Weighting for May 2021: 20%
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.
Paper 3 contributed 20% in SL and 24% in HL to the overall grade in the past. The removal of paper 3 makes significant changes for students taking May 2021 exams.
- Students don’t have to study one of the four options for section B of Paper 3.
- There won’t be any questions about the prescribed practicals or experimental skills as these would be in section A of paper 3. However, IB still expects students to understand and develop these skills therefore, they should be supported by the internal assessment and during teaching of the core content.
- The weighting of paper 1 and paper 2 will be increased by 10% each (see table above). The marks allocated for each paper has not changed so, no change in the duration of the exams expected.
- The weighting of IA is not changed. This is for the benefit of the students as many students may not have equal opportunities to have access to their schools for primary data collection or online sources for reaching secondary data.
- Group 4 Project is no longer a requirement and no evidence is expected to be collected and submitted to IB, although schools are encouraged to continue to do it as it creates an opportunity for the students taking sciences to choose a topic and approach it from different angles and work collaboratively with the other disciplines.
- Students are expected to complete their Creativity, Activity, Service (CAS) before the examination period but IB announced that they will be more flexible on this and left it to schools’ discretion to support their students in completing their work without jeopardizing their health and safety.
IB Chemistry Subject Guide:
About The Exam Content
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.
Time Allocations for SL & HL Students
Topics
Recommended Teaching Hours SL+HL (95 hrs)
Recommended Teaching Hours HL (60 hrs)
Topic: Stoichiometric relationships
Topic: Atomic Structure
Topic: Periodicity
Topic: Chemical Bonding & Structure
Topic: Energetics
Topic: Kinetics
Topic: Equilibrium
Topic: Acids and Bases
Topic: Redox Processes
Topic: Organic Chemistry
Topic: Measurement & Data Processing
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.
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.