• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Organic lab. Comparison of alkanes and alkenes

Extracts from this document...

Introduction

´╗┐Vita Salvioni Guttmann Chemistry III HL 22-10-2012 Organic Lab Data Collection Part I ? Alkanes 1. Volatility of methane, hexane, and paraffin Substance Methane Hexane Paraffin wax Observations Colorless gas, with a smell of sweet burnt alcohol. Clear, colorless liquid. Alcoholic smell, light but pungent. White, oily (waxy) solid. Very malleable, odorless. 1. Solubility of hexane and paraffin in water Substance Hexane + water Paraffin wax + water Observations Hexane when shaken with water does not dissolve. We can tell so because even though both liquids are clear and colorless, we can see a clear line which distinguishes one liquid from the other. The hexane floats right above the water, never mixing, and we can see the line of separation. Paraffin wax when shaken with water also does not dissolve. Even when finely ground, the solid pieces of wax float throughout the liquid and eventually deposit on the bottom of the test tube, never mixing with the water. 1. Combustibility of methane, hexane, and paraffin wax Substance Methane Hexane Paraffin wax Observations When the lighted splint is inserted in the test tube filled with methane, the flame quickly extinguishes itself, with a small spurt of black smoke. Right after, water vapour coats the walls of the test tube. Therefore, combustion occurred, since the water vapour means that H2O and CO2 are produced as bi products. ...read more.

Middle

1. Combustibility of methane, hexane, and paraffin wax 1. Methane CH4 (g) + 2 O2 (g) ï CO2 (g) + 2 H2O(g) * 1. Hexane 2 C6H14 (aq) + 19 O2(g) ï 14 H2O(g) + 12 CO2 (g) * 1. Paraffin wax No combustion reaction occurred - paraffin only changes state: C20H42 (s) + heat ï C20H42 (l) Part II – Comparison of alkanes and alkenes 1. Reaction of the double bond 1. Hexane No addition reaction occurred Concentrated H2SO4(l) C6H14 (aq) + KMnO4 (aq) C6H14 (aq) + KMnO4 (aq) 1. Hexene Concentrated H2SO4(l) C6H12 (aq) + KMnO4 (aq) C3H6O2 (aq) + KMnO2 (aq) 1. Combustibility of hexane and hexene 1. Hexane 2 C6H14 (aq) + 19 O2(g) ï 14 H2O(g) + 12 CO2 (g) * 1. Hexene C6H12 (aq) + 9 O2 (g) ï 6 H2O(g) + 6 CO2 (g) * Part III – Alcohols and Carboxylic acids 1. Oxidation of ethanol reflux 3 CH3CH2OH(aq) + 2 K2Cr2O7 (aq) + 8 H2SO4 (aq) + heat 3 CHâCOOH(aq) + 2 Crâ(SOâ)â(aq) + 2 KâSOâ(aq) + 11 HâO(g) 1. Making esters concentrated H2SO4 CH3CH2OH(aq) + CH3COOH(aq) CH3COOCH2CH3 (aq) + H2O(g) * These reactions are written as complete combustions, but in reality they were incomplete conbustions, as we can tell from the soot (carbon) ...read more.

Conclusion

Therefore, the combustion of hexene requires more oxygen than that of hexane, since the amount of oxygen in the atmosphere remains more or less constant. Part III – Alcohols and Carboxylic acids 1. Oxidation of ethanol The oxidation of ethanol is an oxidation of a primary alcohol. The reaction can occur because all the reaction conditions are present: heat, the oxidizing agent (K2Cr2O7 ) and the catalyst (H2SO4). Therefore, the alcohol (CH3CH2OH) first will form an aldehyde through distilling (low ratio of oxidizing agent to alcohol) but then through reflux it will form a carboxyllic acid (CHâCOOH). We can notice the reaction occurring by observing the changes in the test tube. Initially yellow-orange, the solution then turns green. Also, we notice a change in scent, from a pungent alcoholic scent, to a sweeter, more pleasant smell. 1. Making esters A reaction occurs when the ethanol and the ethanoic acid, aided by the catalyst H2SO4 and heat, form an ester CH3COOCH2CH3 and water. Also here, the reaction only occurs because the reaction conditions were present: heat and catalyst H2SO4. We can notice the reaction occurring by observing the changes in the test tube. The color changes from a warmer color, to a colder, blue-green color. Also, we notice a change in scent, from a pungent alcoholic scent, very unpleasant, to a fruity, sweet and tangy smell like lemon pie. Indeed, esters are used as artificial flavouring, replicsting the smell of fruits. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Chemistry essays

  1. Rates of Reaction Lab

    our raw data involved high percentages uncertainties, in turns making the results of this experiment quite unreliable. The apparatus used may not have been of such accuracy as to which it would provide us with exact and precise values. One main problem encountered in the experiment turned out to be the use of the gas syringe.

  2. Enthalpy of Combustion Lab Report

    However after the ethanol was burnt and the mass of the spirit lamp was once again being recorded, the lamp was warm at the end of the experiment. 4. It was noted that while the spirit lamp was placed on the beaker perpendicularly below the calorimeter containing the distilled water,

  1. A comparison of various proprieary antacids

    On the other hand each mole of magnesium hydroxide neutralizes 2 moles of Hydrochloric acid, that is to say the mole ratio is 2:1. In all, a mole of aluminium hydroxide and magnesium hydroxide neutralize a net number of 5 hydrochloric acid moles.

  2. flame test lab

    The example of use the flame test is to identify the composition of stars by analysing the received light. Evaluation Not all the lines in the spectrum were seen. I found in the literature and internet that for lithium chloride we should see 3 lines in the hand spectroscope (blue

  1. Molar Heat combustion chemistry - investigate the effect of molar mass on the molar ...

    Accepted Values of Molar Heat of Combustion Percentage Difference (%) Methanol 312.92 726 132.01 Ethanol 466.46 1367 193.06 1-Propanol 1037.45 2021 94.80 1-Butanol 1194.44 2676 124.04 1-Pentanol 1127.08 3329 195.37 Conclusion and Evaluation: The aim of this experiment is to investigate the effect of molar mass on the molar heat

  2. Hesss Law Lab, use Hesss law to find the enthalpy change of combustion of ...

    seen that the calculated uncertainty can account for the discrepancy in all the trials. The results obtained from all the trials lie relatively close to each other and also to the table value which means that my experiment was quite precise and accurate.

  1. Strong and Weak Acids And Bases

    The conductivity of the HCl varied with the concentration because the concentration of an acid effects its ionization. The higher the concentration, the more of the acid is dissociated and there are more ions available for conductivity. For example, in this lab, 0.001M HCl was a faint conductor, but 1.0M HCl was a very strong conductor.

  2. The aim of this experiment is to examine the enthalpy of combustion of the ...

    92.5 91.0 150 85.5 88.0 90.0 88.0 165 85.0 87.5 89.5 87.0 180 83.5 87.0 87.0 86.0 210 83.0 86.5 86.5 85.0 Lot of soot was formed on the boiling tube.The color of the flame was light orange .Incomplete transmission of heat is assumed due to the movements caused in the laboratory, which affected the flame and therefore the transmission.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work