For example, the brown crust on atoaste d marshmallow is the result of sugar changing to iffer-ent substances in a mixture called caramel. A change in matterthat produces one or more new substances is a chemicalchange, or chemical reaction. The burning of gasoline in acarâs engine is a chemical change.
How much brain power does the average person use? About only 10% Though an alluring idea, the 10 percent myth is so wrong it is almost laughable, says neurologist Barry Gordon at Johns Hopkins School of Medicine in Baltimorâ¦e.
Yet many people do cling on to the idea that we only use 10% of our brains. The idea is so prevalent that when the University College London neuroscientist Sophie Scott was on a first aid course the tutor assured the class that head injuries are not very serious because of the 10% âfactâ.