Benzene ring: lipophilic, nonpolar, can’t form H-bond. • Referred to table 10: Paracetamol there will be polarity of bonds since there is carbonyl group, OH, NH, the electronegativity will be toward the highest EN which is indicated with arrows on the molecule. Also the polarity of drug is partially since there are no charges. It seems like its partition happens more in lipid because of the presence many non-polar hydrocarbons than polar. It can be ionized in H2O since there is acidic functional groups (phenol and amide).
The aqueous layer was on the bottom because it was denser than the organic layer. The aqueous layer contained the benzoic acid and the organic layer contained the naphthalene. The drying step was partially successful in the experiment because it rid the organic layer of excess water. In the end, the melting point range of the naphthalene was 55-62 °C, unlike the actual determined melting point of 80.2 °C. There is a possibility that less than needed sodium sulfate had been added to the organic layer mixture because the melting point could have been negatively affected by excess water not absorbed by the sodium sulfate.
If the salt is formed from a strong acid and a strong base, such as NaCl, the salt will form a neutral solution, since the anions of the acid and the cations of the base will not react with the water. A salt from a weak base and a strong acid, with NH4Cl as an example, will form an acidic solution. This is due to the cations from the base that increase the hydrogen ion concentration, by donating protons, which is known as a Bronsted acid. When concerning a salt formed by a weak acid and a strong base, such as Na C2H3O2, a basic solution will form. The anions of a weak acid in water will generate hydroxide ions, since the molecule will accept protons.
Rates of reaction of the halogenoalkanes scientific knowledge and understanding: Halogenoalkanes are classified as either primary, secondary or tertiary. In primary halogenoalkanes the halogen atom is covalently bonded to a carbon atom which is bonded to one other carbon, to two other carbons in secondary and three others in tertiary. Apparatus for a reflux Increasing the size of the halogen atom in the halogenoalkane decreases the bond strength, increasing the reactivity of the molecule, as the bond is easier to break. BOND BOND ENTHALPY (kJ mol-1) carbon-fluorine 467 carbon-chlorine 340 carbon-bromine 280 carbon-iodine 240 It can clearly be seen that the bond enthalpy (energy needed to break bond) of the C-X bond decreases as we move down as we go from C-F to C-I. Halogenoalkanes are volatile liquids.
This was done by adding caffeine to water. The caffeine dissolved immediately in water as water is a polar compound. The polarity is due to the dipole interaction formed due to the electronegativity difference between oxygen and hydrogen, where oxygen is more electronegative and thus has a positive charge. Caffeine is polar due to many oxygen-carbon and nitrogen-carbon polar bonds. Since, both compounds are polar, caffeine easily dissolves in water.
A Lewis acid is any substance that accepts a lone pair of electrons.A strong acid is one that breaks apart close to 100% when in solution (example HCl). When dissolved in water, HCl breaks apart into H+ and Cl- ions. Not all acids break apart. A weak acid is/are chemicals that do not break apart well. Acids have a sour taste, they are: corrosive and electrolytes.
Based on (their degree of polymerization and hydrolysis) the commercial grades of PVA can be classified into two classes namely; (a) fully hydrolyzed group (the alcohol groups replaced about the above 98% mole of acetate groups),where in hot water the PVA is soluble and have good film forming characteristics (at lower temperatures the formed films are insoluble in water.) as well as good adhesive properties [25,26]. (b) partially hydrolyzed group (the alcohol groups replaced about 87–89% mole of acetate groups) . At the room temperature the PVA is soluble in water and slightly soluble in ethanol, but in organic solvents the PVA is difficult to soluble (insoluble) . The cross linking of the linear chains of PVA with formaldehyde, boric acid, some salts and other insolubility agents can be turned the PVA adhesive to be a water resistant product
In the lab we produced cyclohexene by dehydrating cyclohexanol using H2SO4. This is an acid catalyzed E1 elimination reaction. The reaction is stabilized by polar protic solvents since it as an E1. A polar protic solvent speeds up the reaction which in turn makes more of the product. Since it was an E1, that means it was a unimolecular elimination.
Esterification is a condensation reaction where two molecules are joined together to form a larger molecule with the simultaneous loss of water. This ester in this experiment is isopentyl acetate formed from acetic acid and isopentyl alcohol. The reaction is catalyzed by hydrochloric acid, a Fisher esterification process, (McMurry, p780-781) but the catalyst affects only the rate of reaction, and not the extent of reaction. The desired product accumulates only if the equilibrium constant is favorable. As it happens, the equilibrium constant for this reaction is rather small (~4) (comparing bond energies in the reactants and products will tip you off as to why the equilibrium constant is so small).
The key bonds broken is C-OH, the oxygen from the carboxylic acid bonds with the hydrogens that will then form water. So, the reaction does not simply just break the H and the R but rather -OH and -OR. This reaction is an equilibrium reaction. Applying Le Chatelier’s principle, if alcohol is used as a solvent to carboxylic acid and have a small amount of water (product), then the reaction would favor the product. On the other hand, if the reaction is to go backwards, whereas the reaction would start from an ester going to a carboxylic acid, then the water would be used as a solvent.