1. Through the eyes, hands touch, Knife Carving, dripping hydrochloric acid and other means to identify the types of rock.
2. Coal is due to changes in the earth's crust, ancient forests have been buried at the bottom, and air separation, and has long been the role of high temperature and pressure.
3. Earth from the surface to the center of the earth can be divided into the core, mantle, crust of three parts.
4. Oil is the remains of ancient organisms in formation through the hundreds of millions of years of evolving changes.
5. Mining method of oil extraction by the open and underground mining.
6. Cause huge losses of iron rust, so people through a variety of technical means to control the rate of iron rust.
7. A candle heating sugar occurs when both the physical changes, chemical changes will occur.
8. Baking soda and vinegar mixture will produce gas, and with the phenomenon of light and heat.
9. Nails and copper sulfate react, the solution of the color lighter.
10. Physical changes occurring substances in the course of a certain chemical changes have taken place.