He was examining chamber photographs of cosmic rays when he realised that the tracks orientation revealed the existence of positively charged particles too small to be protons. These sub-atomic particles have the same mass as an electron, but with a positive charge.
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Make the abstract nature of atomic theory more concrete with these evidence-informed teaching tips
Use these worksheets to develop learners’ understanding of ionic structures and bonding, including symbols and diagrams and how macroscopic properties are related to bonding
Use these worksheets to develop learners’ understanding of metallic bonding, including symbols and diagrams and how macroscopic properties relate to the type of bonding
Use this lesson plan, presentation and student worksheet to recap collision theory, before going on to introduce the Maxwell–Boltzmann distribution.
Identify learning gaps and misconceptions with this set of worksheets offering three levels of support
Identify learning gaps and misconceptions with this set of worksheets offering three levels of support
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