Lesson Plan

• Describe the periodic trends of physical state, melting/boiling points, density, colour and oxidising power down Group VII.
• Explain how electronegativity and atomic size influence halogen reactivity.
• Apply a systematic trend‑based method to predict the properties of an unfamiliar halogen and justify the predictions.

• Projector and screen
• Printed periodic‑table handouts highlighting Group VII
• Worksheet with trend tables and prediction steps
• Whiteboard and markers
• Calculator (optional)
• Sample property data sheet for known halogens

Begin with a short video clip showing the discovery of a “new” halogen to spark curiosity. Review students’ prior knowledge of periodic trends covered in the previous lesson. State that by the end of class they will be able to predict the physical and chemical properties of any Group VII element using those trends.

1. Do‑now (5') – Quick quiz on known halogen properties from the last lesson.
2. Mini‑lecture (10') – Present the trends down Group VII (state, melting/boiling points, density, colour, reactivity, electronegativity) using the projector and diagram.
3. Guided practice (15') – In pairs, students complete a prediction worksheet for a fictitious halogen, following the four‑step systematic approach.
4. Whole‑class discussion (10') – Groups share their predictions; teacher checks consistency with known chemical behaviour.
5. IGCSE exam‑style practice (10') – Students answer two typical questions on trends and reactions.
6. Exit ticket (5') – Each student writes one predicted property for an unknown halogen and the reasoning behind it.

Summarise how periodic trends allow reliable predictions of halogen properties and highlight the key steps of the method. Collect exit tickets as a formative check. For homework, students finish the worksheet and research a real halogen not covered in class, preparing a brief summary of its properties.