Criterion D connects chemistry to the decisions societies make. You explain the science of a real product or process, then judge its benefits and costs for people and the environment.
You explain the science behind a specific real-world solution or issue.
You weigh benefits and drawbacks for people, society, the economy or the environment.
Precise terms, units and symbols, used correctly and in context.
Every idea or figure from someone else is referenced with a recognised convention.
A little of the criterion is addressed. Ideas are basic, partly missing, or not linked to the task.
The main points are there but thin. Some explanations are correct; links to the task or evidence are incomplete.
Mostly accurate, well explained and consistently tied to the task, with only small gaps.
Detailed, precise and justified throughout, with ideas connected and applied to new situations or evidence.
A plain-language guide only. Your teacher marks against the official IB level descriptors.
Discuss the use of nitrogen fertilisers in farming.
Fertilisers help plants grow but they can pollute rivers.
Plants need nitrogen to make proteins, and soluble nitrate fertilisers replace what crops remove, which raises yields and helps feed more people (Source 1). When rain washes excess nitrate into rivers, it causes eutrophication: algae bloom, then decompose and use up dissolved oxygen, and fish die. Applying smaller, better-timed amounts balances food security against river health.
Criterion D is Reflecting on the impacts of science. It is marked out of 8 across 4 strands (D.i, D.ii, D.iii, D.iv). Criterion D connects chemistry to the decisions societies make. You explain the science of a real product or process, then judge its benefits and costs for people and the environment.
Pick a specific case (lithium-ion batteries, fertilisers, plastics recycling) and explain the chemistry involved. Look at the full life of the product: raw materials, use and disposal. Include more than one perspective, for example manufacturers, communities and the environment.
Writing about chemicals as simply good or bad without any detail. Skipping the chemistry and giving only opinions. Using statistics with no reference.
Written by CritABCD for study and revision, in our own words. The official MYP Chemistry guide and assessment criteria are published by the International Baccalaureate. Official IB guide ↗