Full score 5>Junior high school chemistry test questions>The use of the following substances is mainly to use their chemical properties ( ) A. Graphite rods are used as electrodes of dry batteries B. Used for natural gas...
The use of the following substances is mainly based on their chemical properties ( )
A．Graphite rods as dry battery electrodes
B. to use natural gas as fuel
C. Dry ice cloud seeding
D．Copper is used to make wires
The chemical properties of a substance refer to the properties expressed through chemical changes, and the physical properties of a substance refer to the properties that do not need to be expressed through chemical changes. 【Analysis】 A. Graphite rods are used as dry battery electrodes because of the physical properties of graphite—good electrical conductivity. Therefore, the choice is wrong; B. Natural gas is used as a fuel because of the chemical properties of natural gas - it is flammable. Therefore, the choice is correct; C. The use of dry ice in cloud seeding takes advantage of the physical properties of dry ice - it absorbs a lot of heat when it sublimates. Therefore, this option is wrong; D. Copper is used to make wires because of the physical properties of copper—it has good electrical conductivity. So this option is wrong. So choose B.
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