The Kerfox blog https://www.kerfox.app/blog What AQA, OCR, Edexcel and WJEC actually credit, from their own examiner reports, and what the research on revision found at the size it found it. Every claim names the document it came from. en-gb Mon, 07 Sep 2026 00:00:00 GMT Active site, binding site or receptor: the word AQA is waiting for https://www.kerfox.app/blog/active-site-is-not-the-answer https://www.kerfox.app/blog/active-site-is-not-the-answer Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin An enzyme has an active site. An antibody has a binding site. A cell has a receptor. AQA’s examiner reports name the wrong one, four times, on three papers. Denatured, not killed: the enzyme word the mark scheme refuses https://www.kerfox.app/blog/denatured-not-killed https://www.kerfox.app/blog/denatured-not-killed Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin AQA’s GCSE Biology mark schemes credit “denatured” and carry the line “do not accept enzyme(s) killed”. The line, the reason, and the words that are allowed. Less dense, not lighter: six words one chemistry paper refused https://www.kerfox.app/blog/less-dense-not-lighter https://www.kerfox.app/blog/less-dense-not-lighter Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin AQA’s report on the June 2023 A-level Chemistry Paper 3 refuses six answers by name and gives its reasons. Each ruling, and the word to write instead. Why rereading your notes feels like revision and mostly is not https://www.kerfox.app/blog/why-rereading-feels-like-working https://www.kerfox.app/blog/why-rereading-feels-like-working Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin Rereading wins if the test is in five minutes and loses by a week. The experiment that showed it, the survey of what students do, and what the feeling measures. Electron pair donor: the word “pair” is the mark https://www.kerfox.app/blog/electron-pair-donor https://www.kerfox.app/blog/electron-pair-donor Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin AQA’s June 2018 Chemistry Paper 2 report says students who called a nucleophile an electron donor lost the mark. The missing word, and what else was refused. The same hours, spread out: how far apart to space revision https://www.kerfox.app/blog/same-hours-spread-out https://www.kerfox.app/blog/same-hours-spread-out Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin Four hours across four days beats four hours in one evening on any test more than a day away. The evidence, the best gap, and why the worse option feels better. An extra hour of revision costs about eight minutes of sleep https://www.kerfox.app/blog/an-extra-hour-of-revision https://www.kerfox.app/blog/an-extra-hour-of-revision Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin Five hundred students kept diaries for a fortnight. Studying more than usual cost little, and it hurt the next day only when the hour had come out of sleep. How a six-mark chemistry question is actually marked https://www.kerfox.app/blog/how-a-six-marker-is-marked https://www.kerfox.app/blog/how-a-six-marker-is-marked Mon, 07 Sep 2026 00:00:00 GMT Eivan Kolchin A levels-of-response answer is marked twice: for its shape, then for its content. What AQA’s examiners said a Level 3 answer looks like, and what holds it back.