Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
SULFUR, SELENIUM AND TELLURIUM
The elements known commonly as the chalcogens are in the same group (16) as oxygen. They form some compounds same to those of oxygen, but show many differences characteristic of other nonmetal groups. Sulfur is widespread in the Earth's crust, finding as metal sulfides, sulfates, and native or elemental sulfur build by bacterial oxidation of sulfides. Many less electropositive metals known as chalcophiles are collect commonly as sulfide minerals, some important examples are sphalerite (zinc blende, ZnS), pyrites (FeS2), molybdenite (MoS2), galena (PbS) and cinnabar (HgS). Volatile sulfur compounds such as organic compounds and H2S are also collect in petroleum and natural gas. The element is used in bigger amounts for the manufacture of sulfuric acid (see below).
Tellurium and selenium are much rarer, found as minor components of sulfide minerals.
Sulfur has various allotropic forms, the most stable of which are molecular solids containing S8 rings. The elemental forms of Te and Se have spiral chains and are semiconductors. In all of those solids each atom forms two single bonds to neighbors. Sulfur collides directly with halogens (except I) and oxygen, and with many less electronegative elements to form sulfides. The other elements show same properties although reactivity declines down the group.
Positronium consists of an electron and a positron (a particle which has the same mass as an electron, but opposite charge) orbiting round their common centre of mass. Calculate th
1. Acetylation of key proteins is known to correlate with the gene expression in eukaryotes. What class of chromatin proteins is modified? What is the chemical nature of the acetyl
what type of products are gained after electrolytic conduction and in which matter?
your HPLC system has efficiency 1500 theor. Plates, but baseline is very noisy. You have a choice either increase response time or decrease attenuation. what will you choose and wh
n-propyl acetate evaporates rapidly when exposed to air,but water does not.Explain
?
Q. Test for the presence of linseed oil? Hexabromide test is done to know the extent of presence of linolenic acid. In presence of fish oils, which are rich in linolenic acid,
Reaction with Dehydration of alcohol Reaction with H 2 SO 4 [Dehydration of alcohol]: The removal of water from a compound is termed as dehydration. The sequence of simple deh
Question: (i) Differentiate between ionic, metallic, covalent and dipole-dipole bonds. Provide examples in each case. (ii) With regard to electronic con?guration, what do a
synthesis of di and tri substituted benzenes(symmetrical tribromo benzene, 2-amino-5methylphenol, 3-nitro-4-bromobenzoic acid, 3,4-dibromonitrobenzene, 1,2,3-trimethyl benzene) sta
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd