Tuesday, April 14, 2009

3.3 & 3.4: Energy in Reactions

This week we finish our Chemical Reactions unit as we look at bond energy and real-life examples. Be able to...

Describe energy change in a chemical reaction.
Give examples of how living things use chemical reactions to create and store energy.

These are also our choices on Contract 24.

5 comments:

b-ball king 15 said...

i think these sections are easier to understand than the other sections. i get what is needed to balance an equation and why. i understand the reactions like decomposition and synthesis. i also understand endo and exothermic reactions.

rachael said...

When atoms bond they use energy. They either loose or gain energy. Unstable things take more energy too. When bonds break they loose energy, and whenthey reform the release energy.
During photosynthesis plants obtain glucose and they then store it. When we eat the plant we gain engery and store the engery too. When we use the energy its called respiration. Respirtaion is like exothermic, where engery is released. Photosynthesis is like endothermic where it stores engery and more energy is required. Endothermic is recatants+energy=products. Where as exothermial is reactants+product=energy.

Darth Maul said...

energy change in a chemical reaction can be either endothermic (energy is absorbed) or exothermic (energy is released). Photosynthesis uses sunlight and stores the sunlight as sugar.

Keirstin said...

Energy change in a chemical reaction can be exothermic or endothermic. Eothermic releases energy as heat or light and endothermic absorbs energy.

Lauren said...

1. Energy change is endothermic (energy stored) and exothermic (energy released).
3. Photosynthisis in plants and respriation in humans