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Plastics Design Library series include tabulated parameters for the variety of polymers. One of such parameters is a PDL number rating from 0 to 9: 0: solvent dissolved disintegrated 1: decomposition 2: severe distortion; oxidizer and plasticizer deteriorated … 9: highest resistance, no change In the table below I assembled data on thermoplastics ...

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Note that the first reaction would require substantial amount of heat to assure the designated product $\ce{NaAlO2}$ is formed (nowhere near STP): $$\ce{2 Al(s) + 2 NaOH(l) + 2 H2O(g) ->[\pu{\approx 450 °C}] 2 NaAlO2(s) + 3 H2(g)}$$ In aqueous solution the product would be tetrahydroxoaluminate $\ce{[Al(OH)4]-}:$ $$\ce{2 Al(s) + 2 NaOH(aq, conc) + 6 ... 9 Unfortunately, there is no caliper-like tool to measure ionic radii directly. They are determined based on experimental data such as crystal structure or crystal lattice energy using empirical relationships. The exact value would inevitably deviate from one method to another. Pauling [1, pp. 150–152] used a hard-sphere model which doesn't account for ... 0 Well since the ion looks like the helium atom but without 1 proton and since the helium core is approximately 4 times heavier than the hydrogen core and if we neglect the magnetic interactions between core and electrons i would expect it to be 4 times the radius of helium = roughly 125 pm 5 TLDR: Defining the similarity between two molecules is an open field of research, but is fundamentally a subjective question which depends on your context. If you are interested in the similarity of molecular structures, then a graph-based measure might be a logical choice. If you're interested in similarities of reactivity, then a measure incorporating the ... 2 Harsh Jain, It may be a correct reaction, but it is a very complicated one. Let us see what happens when iodine is added to a large volume of an aqueous base in the absence of \ce{H2O2}. It forms iodide and iodate ion. If iodine is in excess, triiodide ion is also formed. The complication arises from adding hydrogen peroxide because it can act as an ... 1 First, the slow action of iodine with water:$$ \ce{I2 + H2O -> H+ + I- + HOI} $$In the presence of \ce{OH-}, the above equilibrium is moved to the right leaving \ce{HOI}. Finally, a fast interaction with \ce{H2O2} (which also occurs with \ce{HOCl}, (see [1, p. 1509]):$$ \ce{H2O2 + HOI -> H2O + O2(g) + H+ + I-}  References Connick, R....

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The bad news is that HPLC columns often die because this ill-treatment. We have had the same issues and eventually several expensive columns was discarded due to the negligence of a student. Acetonitrile, when used above 90% with a phosphate buffer, leads to precipitation inside the column. I have great deal of experience with column manufacturing technology....

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