Reacting ratios: masses | Developing understanding | 14–16 years

Developing understanding is a series of resources that encourage learners to connect their thinking at the macroscopic, sub-microscopic and symbolic levels. This worksheet will develop learners’ understanding of balanced chemical equations and what they mean at the sub-microscopic level in terms of the ratio of a very large number of number (measured in moles) of atoms or molecules reacting or being produced. Based on Johnstone’s triangle, an icon in the margin indicates the conceptual level of thinking that learners need to access in order to successfully answer each question and understanding builds throughout.