Testing Liquids for polarity Essay Example for Free

Testing Liquids for polarity EssayResults and ObservationsLiquidsResultsShape of molecule or Lewis StructureConclusionsDistilled body of water4 cm of warpThe water molecule is very polar. This is because the totally oxygen in the molecule is left with 2 l unmatched jibes which give as a result an enormous negative center. On the some other hand, the two H atoms are positive resulting into a very polar molecule. As a result, the pullulate of distilled water has a quite large deflection which almost went out of the beaker. Heptane2 mm of deflectionThe deflection is very small, almost unachievable to detect. Because of this we washbasin conclude that this molecule is non-polar as no imbibeion towards the charged ruler is shown.Ethanol3 to 4 cms of deflectionIn this case, the deflection of the stream is larger and to a greater extent obvious to human eye. As we brush off see in the structure of the molecule, the oxygen atom is left with 1 lone pair which makes it into a me dium size negative center. However all the carbons and the hydrogen atoms in the left of the oxygen exert a positive charge bigger than the negative charge which makes it polar. However although there is polarity, the stream isnt deflected so much.Propanol3 cm of deflectionAlthough the structure of this molecule is quite similar to the one of HEPTANE, in the case of PROPANOL, we can see an oxygen atom which again is left with 1 lone pair1 which creates a negative center in the decently of the molecule. However, this negativity is balanced thanks to the C and H atoms in the left. This is way this molecule is polar but not enough to deflect the stream so much. This is why it shows a medium deflection of 3 cms.Propanone2 cm of deflectionThis molecule shows as very weak polarity because the only way of this molecule being polar is the double bonded Oxygen-Carbon bond. Oxygen is more electronegative than carbon which gives as a result a very wonky charged dipole. In conclusion, the st ream wont deflect a lot.Ethanoic Acid5 cm of deflectionIn the case of this molecule, we can see 2 O atoms which in total are left with 3 lone pairs which create a gigantic negative center. The rest of the atoms of the molecule arent capable of dealings with these forces so the molecule turns out extremely polar. This is why we can see a very big deflection in this case.Ethyl acetate3 cm of deflectionThis is a moderately polar molecule which shows a medium deflection of the stream. This is because although it has 2 O atoms one of them located on the tweet of the molecule, the lone pairs of these O atoms cant exert that big amount of negative force as to create a very polar molecule. Another cypher is the presence of H and C atoms in both sides of the O atoms which balance the forces of the lone pairs. In conclusion, although its a polar molecule, due to the position of the O atoms and the H and C atoms, Ethyl Acetate didnt deflected that much the streamEthane-1,2-diol4 to 5 cms of deflectionThis molecule is clearly polar because of the great deflection that is caused by it. there are two O atoms each one with a lone pair which creates a very powerful negative center which makes the molecule to be polar.Increasing Order of Polarity DownwardsHEPTANEPROPANONEPROPANOLETHYL ACETATEETHANOLDISTILLED WATERETHANE-1,2-DIOLETHANOIC ACIDCamilo Lovera Trujillo Testing Liquids for polarityEvaluation / ImprovementsLimitations / ErrorsImprovements* wild smell of substances.* Many of the substances we were working with, had a very strong and bad odor which spread all the way over the class. Due to this smell, many of the students implant difficult to concentrate and to be able to record correctly the deflection of the streams. Its better if the students wear any type of mask or mouth concealment so that focusing of students isnt affected by the smell.* Electrically-charged rod* For being able to deflect the stream of the substances it was necessary to have an electricall y charged rod which could attract the stream However, is difficult to keep a fair test in charging the rule or the rod because it was possible that in some cases, the rod was more charged than others. A possible solution to this is to change the rod for a magnet or and object which is already magnetized so that the same tenderness force is kept during all the experiment and no possible inaccuracy in the deflection of the streams can happen.* Deflection* The deflection, in some cases, was difficult to record. Unfortunately, we had no dick to measure the deflection but our own eyes. It was possible to use the ruler but it was also very difficult as everything happened very fast. Due to this, there might be some inaccuracy in the results as they were recorded with what we saw and estimated to be the deflection. Maybe a way to help recording more accurately the information is to use instead of a beaker, a kind of deep transparent tray placed over a ruler so that is easier to measure t he deflectionCamilo Lovera Trujillo Testing Liquids for polarityConclusionIn conclusion, this practical helped us to find the relationships between the Lewis structure or the molecule structure and the deflection the substances caused when they were near to an electrically-charged rod. From the observations and results we can also conclude that the C atoms reduce the polarity of the molecules as they created positive center in the molecule. However, it was thanks to the O atoms n most of the molecules that their polarity was well increased as they were left with lone pairs which helped to create negative center even bigger than the positive ones and due to this, deflect more the streams. On the other hand, theres a final conclusion to be made and is about the order of the polarity. Acids are the most polar substances just after the amides. In the case of Ethanoic Acid, we can see that it makes part of the most polar substances tested in this experiment as a result of the H bondings and the presence of the 2 atoms of O. Going muckle the list we will find Alcohols, Ketones, Aldehydes, Amines, Esters, Ethers and Alkanes.Camilo Lovera Trujillo Testing Liquids for polarityBibliography for Images of Lewis Structure and Molecular Structures* http//www.chem.purdue.edu/gchelp/molecules/heptane.gif* http//www.uni-saarland.de/fak8/schneider/anichem/struktur/ethanol.gif* http//www.fisicanet.com.ar/quimica/organica/ap1/propanol01.gif* http//www2.open.ed.jp/data/37561/01/1221system/images/CH3COCH3.jpg* http//scienceaid.co.uk/chemistry/organic/images/ethanoicacid.jpg* http//www.steve.gb.com/images/molecules/alcohols/ethane-1,2-diol.pngBibliography for additional Information* http//www.elmhurst.edu/chm/vchembook/213organicfcgp.html