• 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
  12. 12
    12

Planning experimental procedures.

Extracts from this document...

Introduction

Skill Area P : Planning experimental procedures: Information: Word equation: Hydrochloric acid (s) + Calcium carbonate (aq) ==> Carbon dioxide (g) + Calcium Chloride (aq) + Water (l) Chemical equation: 2HCl (s) + CaCO3 (aq) ==> CO2 (g) + CaCl2 (aq) + H2O (l) Ratio: 2 : 1 ==> 1 : 1 : 1 Molar ratio in thousandths: 0.002 : 0.001 ==> 0.001 : 0.001 : 0.001 The above equation shows when two moles of hydrochloric acid are added to one mole of calcium carbonate the products made are one mole of carbon dioxide, one mole of calcium chloride and one mole of water. Introduction: In a chemical reaction, the starting materials are called the reactants, and the finishing materials are called the products. If the reactants take a short time to change into products the reaction is a fast reaction. If the reaction takes a long time to change into the products the reaction is a slow reaction. The factors which can alter the reaction are: * Temperature because as the temperature is increased, the ions in the reactants gain more kinetic energy, and so move faster leading to a higher rate of reaction. Thus, there is a greater frequency of collisions and with a greater force i.e. they move more vigorously. So, there is a greater chance the reactants will react and they will then react faster. * Concentration of the reactants because if you increase the concentration of the reactants, there would be more molecules in the same volume and so the molecules would collide more often. So, the energy of the collisions will remain the same (as long as the temperature is kept constant), but the molecules will collide more often (as there are more of them) and so there is a greater chance of them reacting. Therefore increasing the concentration of the reactants would increase the rate of reaction. ...read more.

Middle

? 1 moles / dm3 Volume ( litres ) 0f HCl = 0.002 Moles 1 mole / dm3 Skill Area P : Planning experimental procedures Volume ( litres ) of HCl = 0.002 litres = 2 cm3 However I shall multiply the volume of hydrochloric acid by four to create 8 cm3 instead of 2 cm3 which as it is an easier amount to use. I had to find the volume of carbon dioxide evolved from reacting calcium carbonate and hydrochloric acid .To make 8cm3 for a 0.5 Molar solution of Hydrochloric acid this formula is used: No moles of Hydrochloric acid = Volume ( litres ) ? Concentration ( moles / dm3 ) No moles of Hydrochloric acid = 0.008 litres ? 0.5 moles / dm3 No moles of Hydrochloric acid = 0.004 Moles The ratio of the reactants and products is seen below in the equation: Chemical equation: CaCO3 + 2HCl (s) ==> CO2 (g) + CaCl2 (aq) + H2O (l) Ratio: 1 : 2 ==> 1 : 1 : 1 Molar ratio in thousandths: 0.002 : 0.004 ==> 0.002 : 0.002 : 0.002 The molar ratio in thousandths highlighted in red is the ratio which is needed. It shows when 0.004 Moles of Hydrochloric acid is used 0.002 Moles of Carbon dioxide is evolved. At room temperature and pressure ( RTP ) one mole of any gas will have a volume of 24 dm3 ( 1dm3 = 1 litre = 1000 cm3 ) and the following formula is used: Volume of CO2 = Moles of gas ? 24,000 cm3 Volume of CO2 = 0.002 ? 24,000 cm3 Volume of CO2 = 48 cm3 Therefore the amount of carbon dioxide evolved is 48cm3 when 8cm3 of 0.5 Molar hydrochloric acid is used. To make 8cm3 for a 1.0 Molar solution of Hydrochloric acid this formula is used: No moles of Hydrochloric acid = Volume ( litres ) ...read more.

Conclusion

This prevented it reacting with the hydrochloric acid as well as it should have, and so lowered the rate of reaction. * although the chips had the same mass, they had different surface area. This did not make the investigation a fair test, as those chips with a greater surface area had a higher rate of reaction, and those chips with a lower surface area had a lower rate of reaction. * I could only measure the gas syringe to the nearest cm3 and I found this to be not a very high accuracy. This limited the accuracy of my results. * the room temperature may not have been constant, causing the particles in the hydrochloric acid to have different kinetic energy, causing different rates. * Not every single drop of the hydrochloric acid or the distilled water could be removed from the measuring cylinders, and some of it remained in the measuring cylinder. * It was difficult to simultaneously look at the stop-watch to see the time and look at the gas syringe to see the volume of gas released. Time was wasted in reaction time and this would have affected the results slightly. Further Improvements * more duplicates could have been taken, so that my results would be more reliable. * a burette could have been used to measure out the hydrochloric acid and the distilled water. * more concentrations could have been used. By taking more concentrations, I would have more points on my final graph, leading to a greater accuracy. * the room temperature could be measured every 15 minutes while doing the experiments to make sure that it does not vary too much. this is a test area 19/3/2001 we are looking to see if the computer crashes, if so how long it takes it has now been on for half an hour and it is working very well 2.00pm started- time time now 2.30pm time now 2.45pm timre 3.00pm why is it not crashng, what is the matter time now is 3.15pm I am going to switch off and start again. restarted 3.30pm ...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

    To see how the concentration of acid, reacting with potassium carbonate, affects the rate ...

    4 star(s)

    I will drop a circular tablet of potassium carbonate (which are all the same in all the tests so there is no need to measure surface area or mass) into a conical flask containing the acid and the CO2 produced will be pushed through a delivery tube and bubble into

  2. Investigating the effect of temperature on the rate of reaction between hydrochloric acid and ...

    To overcome this problem I could make sure the acid was the same molar and use a pH probe to be sure. - Some of the gas escaped before I put the bung and gas tube on therefore not giving accurate results.

  1. To investigate the rate of reaction between different concentrations of hydrochloric acid with metal ...

    directed to the ion as a combination of a hydrogen and a water molecule, the norm is to call it the, "the hydrogen ion" and use the symbol H+(aq) ) Below is a diagram of the above formulae, with H3O+(aq)

  2. See how long it takes for sodium Thiosulphate and hydrochloric acid to react at ...

    I will measure it in seconds and the range will vary in each experiment. How to carry out the experiment Step 1- Using a measuring cylinder pour out 50cm� of sodium thiosulphate solution into a conical flask. Keep this measuring cylinder for this solution only to prevent cross contamination.

  1. Investigate how the concentration of hydrochloric acid affects the rate of reaction between calcium ...

    * By counting the amount of bubbles given off. * By timing the reaction until a certain volume of carbon dioxide is produced. * By measuring the amount of carbon dioxide gas produced every 10 seconds. I chose to measure the volume of carbon dioxide gas given off and by measuring the amount of carbon dioxide gas produced every

  2. What Factors Affect the Rate of Reaction Between Hydrochloric Acid and Calcium Carbonate?

    for every mole or percent the concentration of acid is reduced (the line of best fit is a curve and not a straight line). This is because, as the concentration of the acid is decreased, there are more water molecules in a specific volume of the solution, and there will

  1. Rate of Reaction between Sodium Thiosulphate and Dilute Hydrochloric acid

    This graph shows that the time is higher when the amount of Sodium Thiosulphate is much less. This proves that the more Sodium Thiosulphate that is present, the faster the reaction is/will be. On the second graph, it is more or less in a diagonal line going across the page from left to right.

  2. The Effect Of Concentration Of The Reaction Between Sodium Thiosulphate And Hydrochloric Acid

    The fact that there are more water molecules knocking about between the sodium thiosulphate means that collisions between the hydrochloric acid are more likely to occur. My results coordinate very well with my predictions because I predicted that when I added 1cm� of HCl acid and an increase amount of

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