• 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

An Experiment to determine What Factors Affect Neutralisation of 25cm Sodium Hydroxide

Extracts from this document...

Introduction

An Experiment to determine What Factors Affect Neutralisation of 25cm� Sodium Hydroxide Introduction Neutralisation is the reaction between an acid and an alkali that produces a neutral solution - a solution neither acidic nor alkaline. During the reaction, the acid dissociates and produces hydrogen ions, H+, and the alkali dissociates and produces hydroxide ions, OH-. If the number of H+ ions are equal to the number of OH- ions, then neutralisation occurs because there are no extra ions from either the acid or alkali to make it an acidic or alkaline solution - This neutral solution is water: H + OH = H2O. A salt is also produced, depending on what type of acid and alkali you use. The factors that affect neutralisation: - The concentration of the acid - The strength of the acid - The strength of the alkali - The temperature Preliminary Investigation We carried out a preliminary experiment to find the best conditions to carry out an investigation to determine how concentration affects the volume of acid needed to neutralise an alkali. We took three different acids and three different alkalis and tested the volume each solution needed to neutralise either Hydrochloric acid or Sodium Hydroxide. We kept all the concentration of the reactants the same, so the tests would be fair, and the three acids were tested with 20ml of 1M Sodium Hydroxide, while the three alkalis were tested with 20ml of 1M Hydrochloric acid. ...read more.

Middle

Method: 25ml of 1M Sodium Hydroxide will be safely pipetted into a conical flask. This will then be placed onto a white tile underneath a burette filled with Hydrochloric acid. Phenolphthalein indictor will then be added to the alkali. The reading on the burette will be noted down, and then the acid will be run into the alkali and indicator solution. The conical flask will be agitated constantly so the acid and alkali are mixed together thoroughly, and when the indicator changes colour, the acid is stopped running and the volume of acid will be noted down. Each test will be repeated three times for each different concentration of acid, and we will use five different concentrations of acid. Diagram: Apparatus: Hydrochloric Acid of 1.0M, 1.25M, 1.5M, 1.75M and 2.0M Sodium Hydroxide Phenolphthalein Burette Burette filler Conical Flask Pipette Safety bulb White Tile Results These results show the readings on the burette at the start and at the end of the main experiment: Concentration (M) Volume of Acid (ml) Trial 1 Trial 2 Trial 3 Start End Start End Start End 1.0 0.2 25.2 0.5 25.6 0.6 22.0 1.25 0.5 22.3 22.3 44.2 1.2 24.0 1.5 0.2 18.9 18.9 37.7 0.4 19.1 1.75 1.3 16.9 16.9 32.4 32.4 48.1 2.0 1.2 13.7 13.7 26.3 26.3 38.4 Trial 3 for the1.0M acid looked incorrect compared to trials 1 and 2, so we decided to carry it out again: Concentration (M) ...read more.

Conclusion

This would have affected our final results, but we noticed the error and carried out another trial to replace the anomalous one, and this provided sufficient evidence to support my conclusion. Even though this investigation did produce a reliable set of results, we could improve this experiment by using a pH meter and an electronic burette. A pH meter is a device that measures the exact moment a solution becomes neutralised. An electronic burette pours 1ml of the solution inside it every second. agitating the solution could obviously not move at the exact same speed for every separate test carried out, our results could be slightly unfair and inaccurate. By using a machine the experiment would not be affected by human error thus making the experiment more accurate and even fairer. We could also investigate the factor, strength. Strength is the amount of ions free in a solution. If a solution is strong then more ions are free to react. In a weak solution there are some ions that are not free to react. For such an experiment, we could use different strengths of acid to find out how the volume of acid needed for neutralisation is affected by strength. The experiment would be very similar to the investigation we have just conducted, but it will allow us to find out the relationship between volume of acid and strength, and see if it is the same as the relationship between the volume of acid and concentration. ...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

    Chemistry Investigation on neutralisation reaction.

    5 star(s)

    heat change would increase if the molarity would increase and the volumes remain the same. If I can calculate the number of moles of water produced then I found the energy change for producing one mole of water. Then the heat of neutralisation will not change when using more concentrated acids and alkalis.

  2. Marked by a teacher

    Investigate the effect of changing the concentration of sodium hydroxide (alkali) on the volume ...

    4 star(s)

    The use of phenolphalein indicator lowers the risk of obtaining false results as the point of neutralisation is visualised. Dilute hydrochloric acid The acid which will be used to neutralise the alkali (sodium hydroxide. Dilute hydrochloric acid was used to neutralise the alkali because like all acids it contains hydrogen

  1. Marked by a teacher

    Enthalpy of Neutralisation.

    3 star(s)

    Neutralization is used in every day life as well; indigestion or heart burn caused by a build up of hydrochloric acid in the stomach are neutralized by bases (indigestion tablets) containing alkalis such as magnesium oxide. Acidic lakes or fields can be neutralized and hence improved by applying calcium hydroxide (lime)

  2. Antacid Experiment.

    So now, instead, we use Bromophenol blue indicator because we were told it was the best indicator, giving clear results. After we had finished the preliminary work, we started the secondary experiments. We now have to get five different indigestion tablets and do the experiment to check which one works the best, repeating the same experiment three times.

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

    /3 = -46.5 KJmol-1 For HCl and ammonia solution, heat of neutaralisation= -(MC /1000/ 0.03) =1. - ( 60 * 4.2 * 6.5 /1000 / 0.03) 2. - (60 * 4.2 * 6.4 / 1000 / 0.03) 3. - (60 * 4.2 * 6.4 / 1000 / 0.03) = 1.

  2. To investigate the factors that affect the amount energy produced in neutralisation reactions.

    would be compared. This variable could be put under the same category of varying the strength of the acid. This is because as different types of acids and alkalis are being used, the strength of those acids and alkalis would also be being varied in the process.

  1. Titrating Sodium hydroxide with an unknown molarity, against hydrochloric acid to find its' molarity.

    18. Repeat the titration process several more times, until you have three volumes which agree within 0.10cm�. Sources of reference used * Titrimetric analysis for A & S levels (SI Edition), J G Stark, published by John Murray * Chemical Ideas (Second edition), Salters Advanced Chemistry, published by Heinemann * Hazcards publisher?

  2. Analysing the ethanoic acid concentration in different types of vinegars.

    Moles in distillate = 5 x 0.00663 = 0.0332 (3 sf) Ethanoic acid concentration in vinegar sample = ( 0.0332 x 1000)/50 . = 0.663mol/dm3 (3 sf) I will now repeat this for the other distillates: White Wine Vinegar: Titration No.

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