2015-04-01
477
Ozone
Ozone or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope (O2). Ozone in the lower atmosphere is an air pollutant with harmful effects on the respiratory systems of animals and will burn sensitive plants; however, the ozone layer in the upper atmosphere is beneficial, preventing potentially damaging electromagnetic radiation from reaching the Earth's surface. Ozone is present in low concentrations throughout the Earth's atmosphere. It has many industrial and consumer applications.
Ozone, the first allotrope of a chemical element to be recognized, was proposed as a distinct chemical substance by Christian Friedrich Schцnbein in 1840, who named it after the Greek verb ozein "to smell", from the peculiar odor in lightning storms. The formula for ozone, O3, was not determined until 1865 by Jacques-Louis Soret and confirmed by Schцnbein in 1867.
Ozone is a pale blue gas, slightly soluble in water and much more soluble in inert non-polar solvents such as carbon tetrachloride or fluorocarbons, where it forms a blue solution. At –112 °C, it condenses to form a dark blue liquid. It is dangerous to allow this liquid to warm to its boiling point, because both concentrated gaseous ozone and liquid ozone can detonate. At temperatures below –193 °C, it forms a violet-black solid.
Most people can detect about 0.01 mol of ozone in air where it has a very specific sharp odor somewhat resembling chlorine bleach. Exposure of 0.1 to 1 mol produces headaches, burning eyes, and irritation to the respiratory passages. Even low concentrations of ozone in air are very destructive to organic materials such as latex, plastics, and animal lung tissue.
Ozone is diamagnetic, which means that its electrons are all paired. In contrast, O2 is paramagnetic, containing two unpaired electrons.
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Вариант № 5
1. Переведите предложения, обращая внимание на Participle:
1. A chemical compound is a pure chemical substance consisting of two or more different chemical elements.
2. Chemical compounds have a unique and defined chemical structure.
3. Chemical compounds consist of a fixed ratio of atoms that are held together in a defined spatial arrangement by chemical bonds.
4. The answer given in the written form was correct.
2. Определите предложения, в которых частица to является признаком инфинитива и правильно переведите все задание:
1. There are exceptions to the definition above, and large amounts of the solid chemical matter familiar on Earth do not have simple formulas.
2. Crystalline compounds vary in composition due to either the presence of foreign elements trapped within the crystal structure or a deficit or excess of the constituent elements.
3. Everybody knows him to be working on a new book.
4. The lecture was said to be very interesting.
3. Переведите предложения, обращая внимание на страдательный залог:
1. Chemical compound can be separated into simpler substances by chemical reactions.
2. Pure chemical elements are not considered chemical compounds.
3. Mixture's properties are generally closely related to and dependent on the properties of its constituents.
4. A mixture can usually be separated by simple, mechanical means such as filtering, evaporation, or use of a magnetic force.
5. Mixtures can be created by mechanical means alone, but a compound can only be created by a chemical reaction.
4. Переведите предложения с русского на английский:
1. Ей подарили красивый букет роз.
2. Дети не должны играть с ножницами.
3. Разговаривая по-английски, следи за порядком слов.
4. Мне нечего читать.
5. Это произведение будут исполнять на фортепиано.
