u/Available_Lie_5916

they are listed in a2 syllabus but ive seen a few questions regarding them in AS such as the type of catalyst used in internal combustione engines etc. (16/13,M/J/20 paper 1 )so do i need to know about them in as too cuz my sir didnot mention them.

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u/Available_Lie_5916 — 17 days ago