ATAR exams: Chemical formula printed incorrectly on Year 12 chemistry exam that thousands sat

A chemical formula has been printed incorrectly in a question on the final chemistry exam paper which thousands of Year 12 students sat this week.

The mistake — contained in a formula for hyaluronic acid, a popular skincare ingredient — formed the basis of a question worth seven marks.

The chemical formula appearing on the exam paper missed out oxygen, which is a key element of hyaluronic acid.

On the exam, the formula was written as though it had 11 nitrogen atoms and zero oxygen, when it should have had only one nitrogen and 11 oxygen atoms.

High school chemistry textbook author Geoff Quinton said the formula was “clearly incorrect”.

“It will affect the students’ ability to answer the question as the formula is required for the calculation,” he said.

“Most Year 12 students would also know that an organic acid contains oxygen. So the fact that the formula doesn’t contain oxygen is a red flag.

“Students could be unsettled by the fact that they would know there’s something wrong with the formula.”

WA’s School Curriculum and Standards Authority, which sets and marks the exams, confirmed the chemistry paper contained a “typographical error” in question 31 of the short answer section.

“Students will have been able to complete the calculation with the formula provided and demonstrate the required understanding,” a spokesperson for the authority said.

“The marking process is underway and will accommodate a range of student responses, and the School Curriculum and Standards Authority has processes in place to ensure no student is disadvantaged.”

After each exam, examiners and markers review a sample of students’ exam papers to decide if the marking key needs to be adjusted.

Year 12s commenting on social media also complained the chemistry exam was one of the hardest in recent years because it did not include an empirical formula question in the format they had expected.

SCSA appoints a panel of experts, including experienced teachers and subject specialists, to develop the exams.

“ATAR course examinations allow students to demonstrate the concepts and skills that they have learnt in Year 12, with different parts of the course syllabus drawn on each year,” the spokesperson said.

Errors have also slipped through the net in previous years, despite the rigorous checking processes that exam papers go through.

Three years ago, the WA chemistry exam was marred by a comical spelling blunder.

A question in the multiple-choice section of the 2023 chemistry paper referred to “crustations” rather than crustaceans.

Students from schools across WA began sitting their ATAR course written exams on Wednesday, with the last exam scheduled for November 18.