\end{figure}
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\subsection{Boiling Temperature}
-The boiling temperature of the distillate collected appears to be close to the published value (\SI{1.4}{\celsius} lower) and had no noticeable range of boiling temperatures which suggests that the cyclohexene produced was fairly pure. However the true difference in boiling temperature is slightly greater than this since the air pressure in the laboratory was greater (by approximately \SI{0.575}{\kilo\pascal}) than the air pressure for which the literature value is reported at (\SI{101.325}{\kilo\pascal}). This would have slightly elevated the boiling temperature of the product (since the vapour pressure of the liquid would have to be greater for boiling to occur) thus the true difference in boiling temperatures between pure cyclohexene and the product was instead approximately \SI{1.6}{\celsius}. The calculations used to determine these numbers are included in section \ref{sec:boiling-calculations}.
+The boiling temperature of the distillate collected appears to be close to the published value (\SI{1.4}{\celsius} lower) and there was no noticeable range of boiling temperatures which suggests that the cyclohexene produced was fairly pure. However the true difference in boiling temperature is slightly greater than this since the air pressure in the laboratory was greater (by approximately \SI{0.575}{\kilo\pascal}) than the air pressure for which the literature value is reported at (\SI{101.325}{\kilo\pascal}). This would have slightly elevated the boiling temperature of the product (since the vapour pressure of the liquid would have to be greater for boiling to occur) thus the true difference in boiling temperatures between pure cyclohexene and the product was instead approximately \SI{1.6}{\celsius}. The calculations used to determine these numbers are included in section \ref{sec:boiling-calculations}.
-This lower boiling temperature could be due to a combination of factors such as a slight cooling of the vapour as it travelled up the still head or the presence of impurities in the vapour. The product could have been analysed using NMR spectroscopy to definitively identify any impurities in the product, and the thermometer could have been temporarily moved to a position just above the boiling liquid during the distillation in order to obtain a more accurate value for its boiling temperature.
+This lower boiling temperature could be due to a combination of factors such as a slight cooling of the vapour as it travelled up the still head and the presence of impurities in the vapour. The product could have been analysed using NMR spectroscopy to definitively identify any impurities in the product, and the thermometer could have been temporarily moved to a position just above the boiling liquid during the distillation in order to obtain a more accurate value for its boiling temperature. An electronic thermometer could also have been used hence giving a more precise temperature reading and allowing the easier establishment of the range of boiling temperatures for the solution.
-It is likely that there was still a little water impurity in the product after the drying since it was very slightly cloudy when compared to the distilled product. This may have been since the solution was not left to dry for 10 minutes as recommended in the laboratory manual due to time constraints, however a possible improvement to the method could be be grind the drying agent into a fine powder to increase its surface area and thus reduce the time required to dry the product.
+However it is likely that there was still a little water impurity in the product after the drying since it was very slightly cloudy when compared to the distilled product. This may have been since the solution was not left to dry for 10 minutes as recommended in the laboratory manual due to time constraints, however a possible improvement to the method could be be grind the drying agent into a fine powder to increase its surface area and thus reduce the time required to dry the product.
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\subsubsection{Boiling Temperature Calculations}\label{sec:boiling-calculations}
The approximate laboratory air pressure was calculated using an adjusted sea-level air pressure of approximately \SI{102.6}{\kilo\pascal}~\footcite[Pressure at 4:20 PM]{weather-underground-egnt} and laboratory altitude of \SI{55.30}{\metre} above mean sea level~\footcite[Latitude: \SI{54.7683}{\degree}, Longitude: \SI{-1.5711}{\degree}]{os-maps-lab} with equation~\ref{eqn:pressure-diff}.
\end{align*}
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\subsection{Yield}
-The overall percentage yield obtained was very low (\SI{19.4}{\percent}), despite the fairly high percentage of water obtained compared to the theoretical maxima (\SI{69}{\percent}) after the initial distillation. However this water percentage is likely to be a fairly inaccurate measure of yield since the water which formed an emulsion in the organic layer is not represented in this figure and it doesn't account for any water which was originally contained within the reagents (such as the water in the phosphoric acid solution) which was collected.
+The overall percentage yield obtained was very low (\SI{19.4}{\percent}), despite the fairly high percentage of water obtained compared to the theoretical maxima (\SI{69}{\percent}) after the initial distillation. However this water percentage is likely to be a fairly inaccurate measure of the initial yield since the water which formed an emulsion in the organic layer is not represented in this figure and it doesn't account for any water which was originally contained within the reagents (such as the water in the concentrated phosphoric acid solution) which may have also been collected.
-Some of the cyclohexene was lost during transfers both due to some liquid remaining the in previous vessel and due to evaporative losses. To reduce these evaporative losses the flask containing the product could be cooled in an ice bath at all intermediate stages in the experiment, not just during distillation. In addition after the distillations some of the cyclohexene remained in the distillation apparatus. To reduce this a 'chaser' solvent with a higher boiling temperature than the cyclohexene -- such as toluene -- could have been added to the reaction vessel at the end of the first distillation to force any remaining cyclohexene into the collection flask.~\footcite{unmass-cyclohexene-synthesis} This solvent would then be removed from the cyclohexene in the second distillation step.
+Some of the cyclohexene was lost during transfers both due to some liquid remaining the in previous vessel and due to evaporative losses. To reduce these evaporative losses during transfer the flask containing the product could be cooled in an ice bath at all intermediate stages in the experiment, not just during distillation, hence reducing the temperature of the liquid being transferred. In addition after the distillations some of the cyclohexene remained in the distillation apparatus. To reduce this a 'chaser' solvent with a higher boiling temperature than the cyclohexene -- such as toluene -- could have been added to the reaction vessel at the end of the first distillation to force any remaining cyclohexene into the collection flask.~\footcite{unmass-cyclohexene-synthesis} This solvent would then be removed from the cyclohexene by the second distillation step.
The yield calculated is likely to also have been low since not all of the product was distilled for a second time (due to the small size of the round-bottomed flask used) and the second distillation itself was stopped prematurely due to time constraints.
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