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

Theory of Bomb Calorimetry.

Extracts from this document...


Theory of Bomb Calorimetry: The purpose of this experiment is to learn how to apply the laws of thermodynamics to chemical reactions. In this particular experiment we will use a bomb calorimeter to study heats associated with combustion reactions. A bomb calorimeter is a device used for measuring the standard heat of combustion associated with a chemical reaction. The standard heat of combustion for a substance is defined as the enthalpy change, accompanies a process in which one mole of a substance undergoes a combustion reaction with oxygen. It can be found according to equation 1. 1) H- Enthalpy; R - Gas Constant; n - number of moles; U - Internal Energy; s - denotes sample combusted; 0 - denotes standard state (25C, 1bar). ...read more.


2. Make sure all the parts to the bomb calorimeter are at hand. 3. Make a sample pellet (Figure1) using a pellet press. 4. Fuse a metal wire into the pellet of the chemical whose heat of combustion is to be determined 5. Attach the ends of the wire onto the two center poles of the cap that is screwed onto the bomb cavity as show in Figure2. 6. Screw the lid onto the bomb cavity (make sure that the lid is on tight). At this point your bomb should look like the bomb in Figure3. Warning: DO NOT ALLOW THE BOMB TO SHAKE ONCE THE PRESSURE INSIDE IT HAS BEEN INCREASED. 7. Close the bomb valve and raise the pressure inside the bomb with the help of a pressure tank until 25 atm is reached. 8. ...read more.


Allow system to run for 5-10 minutes. 19. Ignite the pellet with the ignition unit and continue to measure the temperature until 5 minutes after the temperature peaks. 20. Unplug all the electrical connections. 21. Next remove jacket lid, and remove the bomb from the water 22. In a designated area of the class room release the gas inside of the bomb by opening the pressure release valve. 23. Once all the gas is removed, unscrew the cap and measure the mass of wire remaining, and ensure that all of the pellet was combusted 24. Begin the calculation process (refer to the theory section). - Calculations In performing the calculations the data recorded in this experiment needs to be used to make a Time versus Temperature graph. The graph should be similar to the following graph. ...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. Find the enthalpy change of combustion of a number of alcohol's' so that you ...

    From my graph devised from the table above, it shows clearly that as the molecular structure/hydrocarbon chain increases so does the alcohol enthalpy change of combustion. For example, the enthalpy change of combustion for methanol is '165.58 Kj mol-1' but for ethanol it is '299.92 Kj mol-1'.

  2. Comparing the enthalpy changes of combustion of different alcohols

    x 100 = 0.26% Water used: 100g; Percentage uncertainty: (0.05/100) x 100 = 0.05% Temperature change: 15.20�C; Percentage uncertainty: (0.05/15.20) x 100 = 0.32% Total error = 0.26 + 0.05 + 0.32 = 0.63% Average error = 0.63% Ethanol 1st Recording Mass of fuel burned: 1.68g; Percentage uncertainty: (0.005/1.68)

  1. Investigating the Enthalpy Changes of Combustion of Alcohols.

    Often, carbon monoxide and carbon (soot) form, reducing the amount of energy released (Appendix B). Incomplete combustion is less efficient that complete combustion. It is this difference (between complete and incomplete combustion) that causes the theoretical graph and my results graphs to separate, and it is a very big separation at around heptanol.

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

    There was also quite a high percentage of error created by the apparatus used. For example the mass of the alcohols was measured on a balance recorded to two decimal places.


    o Spirit burners containing; i. Methanol ii. Ethanol iii. Propan-1-ol iv. Butan-1-ol v. Pentan-1-ol These are the fuels which will be burned to heat up the water in the calorimeter. Method Firstly I will put on my protective clothing and my goggles because of the dangers explained further on.

  2. Comprehensive and Detailed Chemistry notes

    Plastic pipes, guttering Ethanol Solvent, fuel, drinks Polystyrene Plastic packaging, insulation Chloroethane Solvent, refrigerant HYDRATION: Water adds across the double bond to form ethanol (C2H4 + H20--> C2H5OH) HYDROHALOGENATION: Hydrogen chloride reacts with ethylene to form chloroethane (C2H4 + HCl--> C2H5Cl)

  1. Compare the enthalpy changes of combustion of different alcohols

    The difference between the two alcohols is that there are 2 more C-H bonds, 1 more C-C bond and 1.5 more O=O bonds to be broken. There are also 2 C=O bonds and 2 O-H bonds to be formed. The double bonds between O=O and C=O need much more energy to break them because they have a lot more energy.

  2. Determining the change in enthalpy for the combustion of Mg using solution calorimetry and ...

    Hydrochloric acid is extremely corrosive, inhalation of the vapor can cause serious injury, ingestion could be fatal, and the liquid can cause sever damage to the skin and eyes; when working with HCl splash goggles and gloves should be worn, and work should be conducted in a well ventilated area (Cartwright, 2002).

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