Методическая разработка по английскому языку для студентов факультета химии и химической технологии " Simple Chemistry" Алматы 2017
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мет. разработка по химии
| The Tyndall Effect
The Tyndall effect distinguishes colloids from solutions. In a solution, the particles are so fine that they will not scatter light. This is not true for a colloid. If you shine light through a solution, we will not see the beam of light. We will see it in a colloid. For instance, if you have ever played with a laser pointer, you have seen the Tyndall effect. You cannot see the laser beam in air (a solution), but if you shine it into a mist (a colloid, or suspension, actually), the beam is visible. Clouds look white (or gray), as opposed to blue, because of the Tyndall effect - the light is scattered by the small droplets of suspended water. Vocabulary notes the Tyndall еffect – эффект Тиндаля to distinguish – различить fine – мелкий, ясный to scatter – разбрасывать light – свет true – правильно, действительно to shine – светить through – через a beam – луч visible – видимый a laser pointer – лазерная указка a laser beam – лазерный луч air – воздух mist – туман actually – действительно a cloud – облако opposed – противоположный to scatter – разбрасывать, рассеивать a droplet – капелька suspended water – суспензированная (взвешенная) вода Hydrogen Hydrogen is a chemical element. Its chemical symbol is H. Its atomic number is 1. Its atomic weight is 1.00794 u. Hydrogen is a light element in the periodic table. Hydrogen is a very abundant chemical element in the universe. Hydrogen has one isotope. Its boiling point is 20 271 K. Its melting point is 13.99 K. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic diatomic gas. Its molecular formula is H2. Hydrogen readily forms covalent compounds with many non-metallic elements. Hydrogen exists in the Earth in the form of water or organic compounds. Hydrogen plays an important role in the reactions between acids and bases. In ionic compounds, hydrogen has a form of a negative charge. Chemists call it a hydride. Hydrogen cations in ionic compounds have always very complex forms. Hydrogen forms compounds with many elements. Henry Cavendish obtained hydrogen gas in the 16th century. He mixed metals with acids. He also discovered that hydrogen produces water when it burns. In industry people produce hydrogen with the help of the reforming of natural gas. People use hydrogen when they want to obtain ammonia. Also hydrogen gas forms an explosive liquid in the air. People also use electrolysis of water in the production of hydrogen. Vocabulary notes hydrogen водород the universe вселенная odorless без запаха tasteless без вкуса diatomic gas двухатомный газ a base основание a negative charge отрицательный заряд a hydride гидрид complex forms сложные формы to mix смешивать to burn гореть to produce образовывать reforming реформинг natural gas природный газ an explosive liquid взрывчатая жидкость ammonia аммиак production получение жүктеу/скачать 422,31 Kb. Достарыңызбен бөлісу:
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