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Ab aap Whatsapp pe solutions paa saktey h, hum aapko ping karenge. Study Materials. O 3 is also an important component of photochemical smog. O 3 is a stronger oxidizing agent than O 2. It reacts with unsaturated hydrocarbons alkenes in evaporated gasoline to produce aldehydes and ketones which are eye irritants.
Rubber is a polymeric material which contains bonds, and so it too reacts with O 3. Further, ground level ozone and the accompanying smog has proven a significant health concern, irritating and damaging the respiratory system and also having links to asthma [2].
So ozone is beneficial when in the upper atmosphere, but has adverse effects when at ground level. Sulfur occurs in a variety of allotropic forms. At room temperature the most stable form is rhombic sulfur.
This yellow solid consists of S 8 molecules seen in the Jmol below packed in a crystal lattice which belongs to the orthorhombic system listed on the page discussing crystal systems. Click on VdW radii to see a space filling model of the same molecule.
Only near the boiling point of This unusual change in viscosity with temperature is attributed to opening of the eight-membered ring of S 8 and formation of long chains of sulfur atoms. These intertwine and prevent the liquid from flowing.
This explanation is supported by the fact that if the viscous liquid is cooled rapidly by pouring it into water, the amorphous sulfur produced can be shown experimentally to consist of long chains of sulfur atoms.
Selenium is also used in rectifiers to convert alternating electrical current to direct current. Compounds of selenium and tellurium are of little commercial importance, and they often are toxic. Moreover, many of them have foul odors, are taken up by the body, and are given off in perspiration and on the breath. These properties have inhibited study of tellurium and selenium compounds.
Oxygen Since oxygen has the second largest electronegativity among all the elements, it is found in the —2 oxidation state in most compounds. Important oxides have already been discussed in sections dealing with the elements from which they form, and so we will deal only with unusual oxidation states of oxygen here.
H 2 O 2 can be prepared by electrolysis of solutions containing sulfate ions. H 2 O 2 is a weak acid, and it can serve as an oxidizing agent oxygen being reduced to the —2 state or as a reducing agent oxygen being oxidized to the 0 state. Like the peroxide ion, the H 2 O 2 molecule contains an O—O single bond. With the increase in atomic number of electro negativity is decreasd in this group, hence the tendency to show the positive oxidation states will increase.
Chapter Chosen The p-Block Elements. Book Chosen Chemistry I. Subject Chosen Chemistry. Book Store Download books and chapters from book store. Currently only available for. Class 10 Class The p-Block Elements. Why are group 16 elements called chalcogens? Chalcogens means ore forming, as most of the ores in the earth crust are either oxides or sulphides, group 16 elements are called chalcogens.
Oxygen forms about Dry air contains Switch Flag Bookmark. List the uses of neon and argon gases.
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