OCR GCSE Chemistry B · J258
Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Higher), Paper 4 (Higher)
Revise: Use of modelsA representational model uses objects, pictures, symbols or analogies. Ball-and-stick models represent atoms and bonds, while chemical formulae and half-equations represent substances and changes using symbols. These models make otherwise invisible or abstract ideas easier to work with.