1.   A lot of chemical reactions are reversible.

2.   A similar chemical reaction, researchers discovered, could be taking place between the mantle and the core.

3.   Applications here focus on using gigabit networks to combine the processing power of multiple supercomputers for climate and chemical reaction modeling.

4.   Commercially pure ethanol is produced using a variety of chemical reactions to eliminate the water.

5.   Enzymes increase the rate of a specific chemical reaction by lowering the activation energy needed for the reaction to proceed.

6.   Fuel cells, which provide electricity generated by a chemical reaction between hydrogen and oxygen, constitute one part of that research.

7.   Further chemical reactions led to living organisms.

8.   Heat can be produced by chemical reactions or friction.

9.   However, ozone also participates in complex chemical reactions involving trace substances in the stratosphere.