Chemistry TY M. Healy The two major themes will be Energy and Light. At the end of the module students will have presented a project on one of the above themes via powerpoint presentations, posters, models, Song, Teaching materials...

Energy is the ability to do work and produce heat

THERMOCHEMISTRY The study of heat released or required by chemical reactions Fuel is burnt to produce energy – combustion (e.g. when fossil fuels are burnt) CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(l) + energy

What is Energy? Energy Kinetic energy (E K ) Potential energy (E P ) Energy due to motion Energy due to position (stored energy)

EXOTHERMIC & ENDOTHERMIC REACTIONS Exothermic process: a change (e.g. a chemical reaction) that releases heat. Burning fossil fuels is an exothermic reaction

Endothermic process: a change (e.g. a chemical reaction) that requires (or absorbs) heat. Photosynthesis is an endothermic reaction (requires energy input from sun) Forming Na + and Cl - ions from NaCl is an endothermic process

Energy from Food Blackberry Wine 3lb blackberries ½ oz yeast 2.25litres boiling water 2lb sugar Water to Wine –Wine to Water Pour boiling water on to fruit. Leave for 3 days stirring often Strain, add yeast + sugar Syphon off. Leave to mature

FOOD AS A FUEL Sugar + Sulfuric Acid EXOTHERMIC REACTION

TURN WATER INTO WINE DEMO YOUTUBE CLIP

SEE YOUTUBE CLIP

Chemical Reactions Video

LAVA LAMP

This week we're learning how to make lava lamps! These aren't your average lava lamps that need electricity to run. These lava lamps work using chemistry! You will need: 1 Clear plastic bottle 250ml water Vegetable oil Food colouring Alka Seltzer tablets (or any effervescent tablet e.g. Berroca)

What to do: Pour the water into the bottle. Using a funnel, pour the oil in until the bottle is almost full. Wait for the water and oil to separate. Add 10 drops of food colouring to the bottle. The drops will pass through the oil and mix with the water below. Break an Alka Seltzer tablet in half and drop it into the bottle. The tablet will sink to the bottom and start to dissolve. For a true lave lamp effect, shine a torch through the bottom.

The oil stays above the water because oil is lighter, or less dense, than water. Water molecules and oil molecules do not like to mix. When the Alka Seltzer tablet begins to dissolve in the water, it produces bubbles of gas. This is because the Alka Seltzer contains sodium hydrogen carbonate and citric acid. When the tablet begins to dissolve, the sodium hydrogen carbonate and the citric acid react together to produce carbon dioxide gas. As the CO 2 gas bubbles rise through the water and into the oil, they carry some of the coloured water with them. When the blob of water reaches the top of the oil, the gas escapes and the water falls back down through the oil. You can keep your lava lamp going by adding more tablets. The lava lamp can be stored with a lid on. How does it work?