Review of Chemistry HSC Exam 2020

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Chemistry HSC Exam 2020 Review

2020 HSC Chemistry Exam Review

by Aiden Rajratnam, publised 25 November 2020

The 2020 cohort were the second to sit a paper under the new chemistry syllabus. In comparison to last year’s paper, this year’s paper was more challenging, requiring students to apply theory in unfamiliar question formats. The mark distribution for each of the four modules was as follows:

  • Equilibrium and Acid Reactions (Module 5): 17
  • Acid/Base Reactions (Module 6): 34
  • Organic Chemistry (Module 7): 31
  • Applying Chemical Ideas (Module 8): 18
  • Calculations: 28


The mark distribution largely follows the distribution of content in the chemistry syllabus, with a focus on Module 6 this year, especially in the latter half of the paper. The emphasis on calculations observed in last year's paper was also seen in this year’s paper, with approximately 30% of marks allocated to calculations.

The multiple-choice questions were fairly straight forward, targeting major parts of the syllabus. Following a gradual curve of difficulty, questions 16-20 required some critical thinking. The short answer questions, however, were more varied in difficulty. Questions 21, 22, 27, 31 and 33 were standard questions that should be familiar to the large majority of chemistry students.

Questions 23, 24 and 26 examined more niche parts of the syllabus that could easily have been overlooked when preparing for this exam, rewarding those students who meticulously revised the syllabus. Questions 28, 29, 32, 34, 35 and 36 at first glance may have seemed standard, but in actuality required a strong knowledge of the relevant theory and being able to apply it to an unfamiliar situation. For example, question 34 looks similar to the ‘trend in boiling point’ questions often seen in Module 7, however, the question asks to compare the acidity of two acids instead.

The extended response questions were very surprising. As part of the new syllabus, NESA has stated that there will be at least 2 questions in the HSC exam that will be extended response (7-9 marks). These questions are designed to act as differentiators and separate students, especially at the top end. However, this year’s extended response questions are extremely similar to questions seen in the 2019 paper, question 25 resembling last year’s question 29(c) and question 30 a slightly more complicated question 26 (a), highlighting the importance of completing past papers as preparation for exams.

Overall, this paper favoured those with a stronger mathematical understanding, due to many of the latter critical thinking questions being calculations, as well as testing student’s ability to apply theory in unfamiliar situations as opposed to rote learning responses to questions.