Redox and photosynthesis: A simple concept, a complicated procedure

What is the relationship between redox and photosynthesis, and is it as simple as counting the oxidation numbers? Tease your brain with…

Reactivity guidebook

What exactly does reactivity mean? Muse on it with this curated list of O Level TYS questions.

architecture bones building city

Ask a chemist: Were dinosaurs warm-blooded?

Isotopes are chemically similar but not identical. Their subtle difference makes them an excellent tool to find out if dinosaurs were warm…

Green chemistry: NEWSand and NEWOil

The chemistry behind how old things are made new

2019 O Level Pure Chemistry Practical Paper

What can be more practical than revising for practical exam with past-year practical papers?

Negative oxygen ion face mask?

Unmask the truth about "negative oxygen ion face mask"

Purifying water

Read about the Singapore water story, as told through the lens of a chemist, and learn the separation techniques and chemicals involved in…

Salt preparation TYS questions

It's big brain time, as you think backwards from the salt in question to infer the reagents and method

Electrolysis & simple cell TYS questions

Use our Electrolysis Guidebook to conquer these electrifying O Level questions

Enthalpy change TYS questions

Are O Level questions exothermic? Feel the heat as you attempt challenging exam questions.

O Level titration TYS questions

Don't let the difficult question from the 2014 paper be your endpoint. Overcome it here!

The chemistry of rocket science

Learn how combustion and ionisation power rockets

Oxylithe, the oxygen cake of the 1900s

Practise data-based questions as you travel back in time to find out how chemists overcame safety and design problems to deliver fresh air…

Prelim questions on acids

Try out challenging questions from prelim papers to apply what you have learned about acids: dissociation of hydrogen ions, acid formation,…

Stoichiometry & the mole concept prelim questions

Learn stoichiometry and the mole concept by solving problems taken from O Level prelim papers. Answers and explanations are included.