CAIE A Level Chemistry 9701 · Nitrogen compounds
A student prepares a solution of benzenediazonium chloride by adding sodium nitrite and dilute hydrochloric acid to phenylamine kept below 10 °C. The student then warms the mixture to about 60 °C and observes that the solution becomes acidic. Explain why the solution becomes acidic.
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.