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

An investigation into the variables that effect energy changes during a neutralisation reaction.

Extracts from this document...


Nazreen Deller Chemistry Coursework 12/10/02 Aim : An investigation into the variables that effect energy changes during a neutralisation reaction. Background information : A neutralisation reaction is a process whereby the acidity or alkalinity of a substance is destroyed. In order to make a neutral substance you must first determine the ph of the substance, one you have determined whether it is alkali or acid you can then add the same mount of alkali if the substance is acid. This will remove H+ (aq) ions. If the substance is an alkali then you must add the same amount of acid, removing the OH- (aq) ions. It is important that the acid and alkali particles are exactly equal to get a neutral solution. When two chemicals are neutralised, a reaction occurs. This reaction normally results in an event called 'energy change'. An energy change is normally the discharge of energy lost in a reaction. There are two types of energy change If a bond is broken during a reaction, energy is needed , so the surroundings lose heat and reactants gain energy in the form of heat to carry out this action this is carried out through an Endothermic energy change. ...read more.


The equation of this reaction is : HCl (aq) + NaOH (aq) NaCl (aq) + H2O (l) Examples of Neutralisation in everyday life. * Bee sting : This is acidic. It can be neutralised by bicarbonate of soda. * Wasp sting : Unlike the bee sting this is alkaline and can be neutralised by vinegar. * Indigestion : when there is too much acid build up in the stomach. It can be neutralised by an alkaline tablet. Apparatus : * 2 Burettes * 2 Stand and clamp * Funnel * 2 Beakers * Hydrochloric acid * Sodium hydroxide * Distilled water * Universal indicator * Materials and lids for insulation (lids with holes in to fit a thermometer.) * Thermometer. Variables : We will carry out the experiment 6 times with different concentrations of the reactants which are hydrochloric acid and distilled water. Safety: * Safety goggles must be worn when using chemicals and at all times during the experiment. * If any of the chemicals come in contact with skin or clothing it should be rinsed of immediately as they can be irritant or corrosive. ...read more.


Prediction : I predict that the more water and less acid is introduced into the solution will make it weaker and I think that this will slow down the reaction and it will cause less rise in heat. Results Table : Hydrochloric Acid (ml) Distilled Water (ml) Sodium Hydroxide (ml) Temperature Before (degrees C) Temperature After (degrees C) Difference (degrees C) 25 0 25 19 28 9 20 5 25 18 27 9 15 10 25 17 25 8 10 15 25 16 23 7 5 20 25 16 20 4 0 25 25 15 17 2 Conclusion: As less acid and more water is introduced to the sodium hydroxide the temperature decreases as does the difference in temperature. When a solution is neutralised it takes part in an endothermic energy change, this means that the solution gives out heat if the reaction is more violent then there will be more heat produced. The results as I predicted should go down in temperature as the hydrochloric acid is decreased and the water is increased. Evaluation: My results have been conclusive to scientific evidence and my prediction. If I could re- do the experiment I would use better insulation and better measuring equipment. ...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)

    you have to break existing bonds and then make new bonds between all the atoms in the mixture. This requires energy. Different acids and alkalis will need different amounts of energy to start the reaction, and will give out different amounts of energy when the have finished reacting.

  2. Marked by a teacher

    Investigating The Energy Change During A Neutralisation Reaction.

    4 star(s)

    Neautralisation reactions are usually exothermic. Acids are compounds of non-metals with simple molecular structure. They all contain hydrogen (H) covalently bonded to other elements. Acids are also soluble in water and produce solutions with a pH of less 7. They will turn litmus paper red and turn universal indicator an orange/red colour.

  1. Marked by a teacher

    Enthalpy of Neutralisation.

    3 star(s)

    This should mean hydrochloric acid and sulphuric acid should leave chloride and sulphide salts as well as pure water. Some examples of neutralization and its products found in labs are: * Nitric acid + magnesium oxide magnesium nitrate (salt) + water * Hydrochloric acid + calcium hydroxide calcium chloride (salt)

  2. To investigate the effect of concentration on the temperature rise, heat evolved and heat ...

    of neutralization of 2 M concentration = 2559.38 J / (1 M X 0.05 dm3) = 2559.38 J / 0.05 mol = -51,187.5 J or -51.1875 KJ Heat of neutralization of 3 M concentration = 3980.30 J / (1 M X 0.075 dm3)

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

    - (60 * 4.2 * 5.6 /1000 / 0.03) 2. - (60 * 4.2 * 5.5 / 1000/ 0.03) 3. - (60 * 4.2 * 5.5 / 1000/ 0.03) =1. -47.0 KJmol-1 2. -46.2 KJmol-1 3. -46.2 KJmol-1 To find an average of these figures: - (47.0 + 46.2 + 46.2)

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

    Record the temperature rise. Perform this experiment for the rest of the acids. Diagram for preliminary experiment Results of preliminary experiment Sulphuric Sodium Hydroxide 20.0 20.0 32.0 12.0 Nitric Sodium Hydroxide 21.0 20.0 28.0 7.5 Hydrochloric Sodium Hydroxide 20.0 21.0 0.0 7.5 Ethanoic Sodium Hydroxide 20.0 21.0 27.0 6.5 Methanoic

  1. Investigate a neutralisation reaction between hydrochloric acid and sodium hydroxide.

    Here is how I diluted the acid. Molar (M) Volume of hydrochloric acid (Cm3) Volume of water (Cm3) 1.0 10 0 0.8 8 2 0.6 6 4 0.4 4 6 0.2 2 8 Method 1. Collect all the apparatus needed as indicated from the apparatus list.

  2. Investigation into the efficiency of various indigestion tablets.

    (1mol) Mass of CaCO3 in powder (0.25g) = n x mm = 0.001135 x 100 = 0.1135 g Mass of CaCO3 in powder (1.0g) = 0.1135 x 4 = 0.454g = 454 mg Mass of CaCO3 in tablet (1.22675g)

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