Atoms and atomic theory
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English-for-Chemistry-1-After-lesson-1
| …(11)… and others cause pollution. Only through studying chemistry, can we begin to
discover ways to produce chemicals that are sustainable and not …(12)… to the natural world. In summary, we can now that we're all chemists. From cooking food to cleaning ourselves, we make choices everyday based on the way chemicals work. Chemistry is also important for the creation of medicines and environmental issues. By doing …(13)… in chemistry, we can find new cures for diseases as well as better chemicals to use in our natural environment. Chemistry can help change the world. 8.2 Reading: Your alarm rings early, and you are groggy from sleep but eager to begin working on a chemistry assignment that’s coming due. Chemistry has taught you that there are interesting answers to questions you might once have considered silly and childish. Preparing tea, for example, now makes you wonder why the boiling water bubbles and produces steam while the teakettle retains its original shape. How do the tea leaves change the color of the water while the teabag remains as full and plump as ever? Why does sugar make your tea sweet, and why is the tea itself bitter? You settle down with tea and newspaper, and the wondering continues. An article about methyl bromide, a widely used pesticide, says some scientists think it damages the ozone layer. What are methyl bromide and ozone? How does one destroy the other, and why should we care? How can we know if the ozone really is being depleted? Later, as you drive to the library to get some books you need to complete that chemistry assignment, you wonder why gasoline burns and propels your car down the road. How does it pollute the air we breathe and what does the catalytic converter do to minimize the pollution? At the library, you wonder why some books that are hundreds of years old are still in good shape while other books that are only 50 years old have pages that are brown, brittle, and crumbling. Can the books with damaged pages be saved? Chemists can answer all these questions and others like them. They are scientists who study the structure of material substances - collectively called matter - and the changes that they undergo. Matter can be solid like sugar, liquid like water, or gaseous like the exhaust from your car’s tailpipe. tải về 0.52 Mb. Chia sẻ với bạn bè của bạn:
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