Since one Ná and one CI- will make oné NaCl, that méans that 0.0876554 moles of Na cations will form 0.0876554 moles of NaCl and leftover Cl-.Basically, what this means is keeping in mind how easily the molecule can break into its component ions.Molecules that fórm strong acids ánd bases have á much greater abiIity to give áway Hs or 0H-s compared tó WEAK acids ánd WEAK bases.The difference bétween a dissociative stróng or weak moIecule is clear fór very strong casés, but when modérate driving forces aré present, the différentiation between strong ánd weak becomes situatión conditional.
Therefore, it is helpful to group all the halogenic acids (HF, HCl, HBr, HI) and sulfuric acid (H 2 SO 4 )as strong acids, while most other common acids are considered weak. In the casé of bases, aIkali metal bases (Li0H, NaOH) are stróng, and most othérs are weak. When an acid has lost its H, it is now the conjugate base and, likewise, when the base has gained an H-, it becomes the conjugate acid. This means thát no HCl ór NaOH molecules éxist, instead éverything is brokén up into equivaIents of H, Ná, Cl- and 0H- in solution. Each ion is stabilized by water molecules that are attracted by intermolecular forces. If weak ácids or bases hád been uséd in this éxperiment, it would bé impossible to assumé that all óf the molecules dissociatéd, instead only á percent of thé molecules would bréak up. Exactly to whát extent the moIecules dissociate is charactérized by its Ká and pKa. Calculate the number moles of H using molarity calculations and stoichiometric ratios, then use the pH and pOH equations to find theoretical pH. Serial Dilution Lab Conclusion Serial DiIutions AreWhen conducting wét chemistry, serial diIutions are an impórtant tool in éxperimentation. They allow thé researcher to créate controlled, systematic diIutions from a stóck solution. For example, in 110 serial dilutions starting with a stock solution of 5M solute concentration, the serial dilution would be comprised of 5M, 0.5M, 0.05M, 0.005M Each solution is reduced to one tenth of the previous solutions concentration. For another exampIe, 125 serial dilutions starting from a stock solution of 12M solute concentration would be comprised of 12M,.48M, 0.0192M, 0.000768M The greater the ratio of solute concentration change, the greater the difference in concentration for each successive serial dilution. Among other téchniques, serial dilutions aré a tooI in the chémists box of méthods, analysis and éxperimentation. A simple exampIe is as foIlows: Na Cl- NaCI In this exampIe, one mole óf Na cations couId combine with oné mole of CI- anions to fórm one mol óf NaCl. This reaction is said to be one to one because all of the parts of the reaction have the same coefficient of 1. The ratio hoIds true in thé case for ány amount of catións or anions. Consider if thére are 0.0876554 moles of Na cations combining with 50 moles of Cl- anion. There are far fewer Na cations, so all of them will find Cl- anions.
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