• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11

Determine the Enthalpy of Neutralisation for the following there Acids, H2SO4, HNO3 and H2SO4

Extracts from this document...

Introduction

A level coursework Determine the Enthalpy of Neutralisation for the following there Acids, H2SO4, HNO3 andH2SO4 Introduction Acid and bases have a very important property that is that they are able to cancel each other out when mixed together in the right proportions, this reaction is called a neutralisation reaction, which can be an exothermic reaction . The standard enthalpy of neutralisation is the heat absorbed per mole when an acid and a base react to form water under standard conditions. In this experiment I will be investigating the values for enthalpy of neutralisation of the three strong acids (HCl, HNO3 andH2SO4) Scientific Background information As explained before, neutralisation happens between an acid and a base. Neutralisation is the formation of water from hydrogen and hydroxide ions H30+(aq) + OH-(aq) --> 2H20(aq) According to Arrhenius' theory 'neutralisation occurs because equal mols of hydrogen ions in the acid are equal to the mols of hydroxide ions in the base so the two react completely to form water'*1. Neutralisation of HCl and NaOH: NaOH(aq) + HCl(aq) --> NaCl(aq) + H2O(l). Neutralisation of HNO3 and NaOH NaOH(aq) + HNO3(aq) --> NaNO3(aq) + H20(l). Neutralization of H2SO4 NaOH(aq) + H2SO4 --> Na2SO4(aq) + H20(l) The enthalpy of neutralisation for strong acids are similar, because 'strong acids fully disassociate in water therefore all hydrogen ions and all hydroxide ions react to from water ...read more.

Middle

First of all I will be careful in pouring the acid so that It does not go onto my skin when in contact with acids the skin will irritate * If the acid gets into contact with the eyes it will be difficult to remove the acid, which would then cause serious damage to the eyes. So for this reason I will wear safety goggles at all times during the experiment, or if any explosions occur I will not damage my eyes. Using the results * Plot the temperature(�C) -vs- time(min) graph. * Use the diagram to draw a line of best fit for the temperature of the solution before addition of alkali and draw the line of Best Fit after addition of alkali as shown in the diagram below * Use this to find the initial temperature and the maxixmum temperature, hence the temperature achange Obtaining Results: Results Tables HCl Conc: 1 moldm-3 Amount of acid added: 25cm3 Final temperature: 27.4�C ?T : 5.9�C Time (min) Temperature of Solution / �C 0 21.0 1 21.5 2 21.5 3 21.5 4 22.0 5 24 6 25.0 7 26.5 8 27.0 9 26.5 10 25.5 11 24.5 12 24 13 23 HNO3 Conc: 1 moldm-3 Amount of acid added: 25.5 Final temperature:25.9�C ?T : 5.9�C Time (min) ...read more.

Conclusion

Firstly the low values of Enthalpy of neutralisation which are result of heat being lost the surroundings before the temperature rise has been recorded. This is probably due to the fact that I didn't use a lid on the polystyrene cup. If I was to repeat the experiment I will make sure I do this to keep in as much heat energy in the cup. 2) Secondly my stirring for the diff acid experiment was not consistence. I may of stirred it differently for all the others, this would mean that more or less heat would of escaped, then required, which affect my thermometer readings. There are 3) Thirdly In my attempt to reduce the time needed to complete my experiment I didn't rinse the measuring cylinder which I was using to measure out the volumes of Acid. Of course this must have led to some contamination of different acids with the acid I was measuring. Next time I will ensure that I wash all apparatus and rinse in appropriate solutions each time I repeat the experiment for different acid. Lastly the thermometer I was using was inaccurate by o.5C. The faulty thermometer would have no effect on the calculated enthalpy of neutralization because the thermometer read 0.50 degrees low consistently so it would have had no effect of the ?T, however next time I will make sure I use a thermometer which is correct to avoid any confusion. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Aqueous 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 GCSE Aqueous Chemistry essays

  1. Marked by a teacher

    Investigating The Energy Change During A Neutralisation Reaction.

    4 star(s)

    Heat flows between system and surroundings until the two are at the same temperature. Enthalpy Under conditions of constant pressure the heat absorbed or released and termed enthalpy or heat content. Enthalpy is not measured directly, we are concerned about the heat added or lost by the system which is the change is enthalpy.

  2. Marked by a teacher

    Enthalpy of Neutralisation.

    3 star(s)

    The correct term for heat content is enthalpy, H. Usually, this change in the heat content or enthalpy is shown by a change in temperature. Indeed, the change in temperature when substances react often provides evidence that a chemical change has taken place. The experiment technique used for the determination of enthalpy is calorimetry, which is being used for this experiment.

  1. Explain how the enthalpy change of neutralisation can be used to determine the relative ...

    Hydrogen fluoride (dissolving in water to produce hydrofluoric acid) is also a weak inorganic acid. Apparatus: * 3 - 100cm3 beakers * 50cm3 burette * Coffee cup calorimeter: This is a simple, inexpensive device used in many general chemistry labs. It is made of two nested and capped cups made of Styrofoam; making it a very good insulator.

  2. Investigation to find out the factors affecting heat of neutralisation, and then choosing one ...

    However having said that I expect that some heat will be lost to the surroundings, and so the heats of neutralisation I attain will probably be lower than those found in a data book. * I also know from preliminary work that the various different acids and alkalis of different

  1. Investigating Neutralisation.

    + Na+ OH- (aq) Na+ Cl- + H2O Erase spectator ions H+ (aq) + OH- (aq) H2O (l) Exothermic reaction This is the ionic equation for the neutralisation of any acid and alkali. When the solutions of acid and alkali are mixed, hydrogen ions, H+ (aq), and hydroxide ions, OH- (aq)

  2. Investigation into how much heat is produced in a neutralisation reaction.

    To do this we multiply by 20. 1 mole = 2625 x 20 = 52500Jmol This result shows that the degree of accuracy is quite high. Equipment Safety glasses Pipette filler Pipette 25 cm� Polystyrene cup with lid Beakers Sulphuric acid 75 cm� Potassium Hydroxide 125 cm� Stopwatch Thermometer 0�C-50�C, 0.1�C gradients Burette Water Prediction I predict

  1. Specific Heat Capacity

    Then I will take the temperature of the boiling water, after the five minutes are finished, and quickly transfer the metal A to the water in the calorimeter C. I will then record the temperature every 30 seconds for five minutes, whilst stirring the water.

  2. Titration with a primary standard.

    If I had measured 50 cm3 with the same measuring cylinder, the error would have been 0.5/50 x 100 = 1% so the bigger the reading the smaller the percentage error. If I use a big measuring cylinder the graduations may be every 2 cm3.

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