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The anions and cations can be varied to get the required end product. Ionic liquids have large anions and cations of low symmetry to reduce the lattice energy and reduce the melting point of the salts. Anions contribute towards the functions and chemistry of ILs and cations contribute towards the variable physical properties and stability of ILs (Bӧhme 2006). Ionic salts can be simple salts i.e. made up of one type of anion and cation or binary ionic liquids which are a mixture of two salts with varying melting points depending on their composition.
Ionic liquids are used to substitute traditional solvents like volatile organic compounds (VOC’s) for their variable properties, low energy inputs and reusability. They are also used to extract various compounds such as metal ions, biomolecules and organosulfurs by using two phase extraction. The most commonly studied systems contain ammonium, phosphonium, sulfonium, pyridinium, imidazolium and pyrrolidinium cations. Common anions include hexafluorophosphate [PF]6-, tetrafluoroborate [BF]4-, bis(trifyl)imide [NTf]2 and chloride, Cl-.
Ionic liquids help in minimizing and eliminating waste, improves chemical syntheses and extractions or separations (Holbrey, Turner & Rogers 2003). The reaction solvents are reusable and do not diminish in content which is a major advantage over traditional solvents that are sometimes volatile like the VOC’s.
However, the most important feature of these ionic liquids that has led to the great amount of interest in them is the ease with which these can be manipulated to suit the needs of a particular reaction. Most of the properties that are attributed to reaction solvents can be redesigned to reduce or eliminate the losses in solvents and the reaction path can be modified to optimize reactions. This can be useful in recovering and reusing
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Even households generate hazardous waste from items such as batteries, used computer equipment, and leftover paints or pesticides.
The waste can harm humans, animals, and plants if they encounter these toxins buried in the ground, in stream runoff, in groundwater that supplies drinking water, or in floodwaters, as happened after Hurricane Katrina.
One mole of beryllium weighs 9 grams, therefore we have 0.1 mole of beryllium if the mass is 0.9, one mole of oxygen weighs 16 grams therefore we have 7.3/16 moles of oxygen and finally we have 4.5 grams of aluminium therefore we have 4.5/27 moles of aluminium.
The Carbon atom closer to the viewer is called the ‘proximal’ and the one further the ‘distal’ atom.
All staggered conformations have lower strains compared to eclipsed conformations. The staggered (anti) conformation is the most stable
ton in his atomic theory states that atoms of any one element are all exactly like in every respect including masses but different from atoms of every other element. According to this theory since ethyl alcohol and dimethyl ether have the same composition by masses and exactly
These brain functions are responsible for mental, emotional and motor skills. Irregular activity on neuro-transmitters in the brain would be one of the reasons for mental and emotional disorders that may affect person’s emotional and physical behavior. Changes in
t to be accurate because the minimum measure of mass according to the apparatus is 0.0001, therefore if the measure was exactly 11.439 g then this should have been written as 11.4390 g.
The Millikan experiment is used to measure the electric charge of electrons by carefully
The American Thyroid Association (2005b) added that there is no single best treatment for patients with hyperthyroidism since the treatment may depend on factors such as age, type and severity of hyperthyroidism,
Q4. NO+ ligand would form a bent i.e. V-shaped geometry in a metal complex. More electrons are pulled to N in the radical hence the metallic ion would be attracted to the partially negatively charged N atom. The lone pair electron in the N atom cause attraction of positively