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

To find out the enthalpy change of combustion by burning butanol and enthalpy.

Extracts from this document...

Introduction

Enthalpy Change of Combustion Aim To find out the enthalpy change of combustion by burning butanol and enthalpy. The standard enthalpy of combustion is the enthalpy change when one mole of an element or compound reacts completely with oxygen under standard conditions. In practice it is not possible to achieve complete combustion under standard conditions measurements are taken under experimental conditions; then a value for the enthalpy change is determined. During chemical reactions when bonds break, energy is absorbed. When bonds form, energy is released. The enthalpy change of combustion is the amount of enthalpy change when one mole of an element or compound reacts completely with oxygen under standard conditions the standard conditions is the pressure of 100kPa and temperature of 298k. ...read more.

Middle

I measured out 500cm3 of with a measuring cylinder and then I poured this into the calorimeter. I placed the thermometer in the calorimeter and then I measured the temperature of the water and then placed the burner underneath the calorimeter and lighted the burner. I used a stirrer through out to even the temperature of the H2O When bubbles appeared in the calorimeter I put out the burner and took the temperature again. This was to make sure no H2O were lost due to boiling thereby keeping the mass of H2O constant. This was repeated again for the ethanol I made sure I used different burners so not to mix the ethanol and butanol. ...read more.

Conclusion

44.1Kj ? 46g ? x x = 44.1 x 46 2.25 = 901.6Kj So 901.6 Kj Of any given amount by 1 mol = ?HC = 901.6 Kj mol-1 Results for butanol Mass of burner 109.01g Mass of burner and ethanol 110.52g Mass of ethanol 1051g Volume of water 500ml ==> 500g Temp of water at start 27 oC Temp of water at the end 42 oC Temp rise 15oC E = mc?T = 500 x 4.2 x 15 = 31500j ? 31.5Kj 1 mol of butanol =74g 1.51g ? 31.5Kj ? 74g ? x Kj x = 74 x 31.5 1.51 = 1543.7Kj mol-1 So 1543.7Kj of any given amount by 1 mol = ?HC = 1543.7Kj mol-1 Alex Mcghie ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Organic 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 AS and A Level Organic Chemistry essays

  1. The aim of this experiment is to investigate the enthalpy change of combustion for ...

    Results I can calculate the enthalpy change of combustion of the alcohols using the equation H =mc t (where m is the mass of water, c is the heat capacity of the water which is known as 4.18 and t is the increase in temperature.)

  2. Find the enthalpy change of combustion of a number of alcohol's' so that you ...

    There is a danger of very serious irreversible effects though inhalation, in contact with the skin and if swallowed. If swallowed: Wash out mouth and give a glass or two of water. Seek medical attention if victim shows drunken symptoms. If vapour inhaled: Remove victim to fresh air to rest.

  1. Compare the enthalpy changes of combustion of different alcohols

    An example of this maybe if when I measure the calorimeter with the water already filled, this would not take into account the mass of the calorimeter. The other type of error is random error. This is one that I cannot control and is sometimes inevitable.

  2. Comprehensive and Detailed Chemistry notes

    solubility of carbon dioxide in water under various conditions as an equilibrium process and explain in terms of Le Chatelier's principle Temperature has quite a large effect on the solubility of Carbon dioxide. Le Chatelier's principle generally states that any if any change occurs in the system, the system will

  1. The Relationship Between The Number of Carbon Atoms In An Alcohol And Its Standard ...

    Overleaf is a table showing the ?H data that I have worked out for all of the alcohols. Alcohol Formation Reactants (KJ) Products (KJ) ?H (KJ/Mol) Methanol CH3OH 2803 3338 -535 Ethanol C2H5OH 4719 5750 -1031 Propan-1-ol C3H7OH 6635 8162 -1527 Butan-1-ol C4H9OH 8551 10574 -2023 Pentan-1-ol C5H11OH 10467 12986

  2. Determination of the Enthalpy Change of a Reaction

    However, one of the main sources of error would have been the use of the lab thermometers which had small graduations and a large temperature range providing inaccurate methods in which to measure temperature changes. The basic thermometer comprises of a coloured liquid filled capillary tube which when heated increases

  1. Investigating the Enthalpy Changes of Combustion of Alcohols.

    the enthalpy is positive. The total energy needed to break the bonds is: (3 x 413) + 336 + 464 + (1.5 x 498.3) = +2786.45 kJmol-1 This is the amount of energy needed to atomise one mole of methanol.

  2. I am going to investigate the difference in enthalpy of combustion for a number ...

    The calorimeter has a mercury thermometer in it, which are very accurate, this will be used to measure the water temperature. I have decided that the calorimeter should be held 1cm above the top of the flame produced by the burning alcohols as so to keep the experiment fair, this being as apposed to having it at a random height.

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