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

Investigation on how the rate of reaction changes as the concentration of an acid changes

Extracts from this document...

Introduction

Chemistry Coursework 01 May 2007 Alex Hall (J) Investigation on how the rate of reaction changes as the concentration of an acid changes Skill P : Planning The investigation that we are studying in this piece of Coursework, is how the rate of the reaction between Magnesium and Hydrochloric Acid changes, as the concentration of the Acid is decreased. The equation for this investigation is as follows: Mg (s) + 2HCl (aq) MgCl2 (aq) + H2 (g) I predict that as the concentration of the acid decreases, the rate of reaction will also decrease. Collision Theory says that the more concentrated the reactants, the more collisions will occur. This also explains why the reaction is quickest at the start; it is because the reactants are in their most concentrated state. As the reaction progresses, the concentration of the reactants decreases, and therefore so does the rate of the reaction. In order for the reaction to take place, the particles must collide; and secondly, the smallest amount of energy, the activation energy must be reached. If the activation energy is very high, then there will be a small number of particles able to react, and therefore the reaction rate will be slower. ...read more.

Middle

I am going to keep the length of the magnesium at a fixed length of 5cm. From my preliminary work, I can see that the yield of 5cm of magnesium, when reacted with hydrochloric acid, is enough to give me clear results when I come to plot the graphs. * The third and final variable is whether or not I use a catalyst to speed up, or slow down my reaction. A catalyst is a chemical which speeds up (or slows down) a chemical reaction. A positive catalyst lowers the amount of activation energy required, so the reaction happens faster, the catalyst is not 'used-up' during the reaction. For this particular investigation, I am not going to use a catalyst. As I have mentioned earlier, I am going to change the concentration of the acid, by adding water. I will need to make sure that I measure the amount of acid and water correctly. When I add some water to the acid, I will need to be certain that the two liquids are evenly mixed together in the test tube, I will do this by shaking the test tube. ...read more.

Conclusion

* 20 cm� acid + 30 cm� water * 20 cm� acid + 40 cm� water * 20 cm� acid + 50 cm� water The reason behind repeating the experiments is so that if in the first experiment for the lowest concentration, the magnesium is dirty; it may not produce accurate results. So in the next section, I am going to display my tables with the original and repeat experiment, and the averaged result. The graphs in the analysis will make use of the average results. There are a few safety measures that I must take, when conducting this investigation. * We must wear our safety goggles and lab coats. * Hydrochloric Acid may burn clothes and skin if it comes into contact with them. * When the two chemicals are mixed, an impurity may cause a small explosion, so if we are wearing our safety goggles, the chance of anything getting into our eyes is greatly reduced. * Most chemicals are dangerous if swallowed, therefore we must not taste any of the products or reactants, and we must also not put a pen or any other item into our mouths because they may have been in contact with one of the chemicals. ...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 coursework

    4 star(s)

    This part of my conclusion does not support my prediction. Evaluation The procedure used to carry out the experiment proved to be excellent, although the only problem was trying to establish the end point of the experiment.

  2. See how different concentrations of Hydrochloric acid change the rate of reaction with a ...

    Altogether I tested 5 different concentrations of hydrochloric acid. 0.5M, which was the lowest concentration of acid that I used, there was only a tiny amount of gas evolved, but the time taken for the magnesium to completely react was over 700 seconds. 2.5M hydrochloric acid, which was the highest concentration that I used, produced the fasted rate of reaction.

  1. Antacid Investigation.

    of acid To change dm3 into cm3 you times it by 100. Calculations for Settlers, Superdrug and Rennie rap- eze . Moles of antacid= 500 mg (0.5g) divided by 100 (RFM) = 0.005 moles Number of moles= 2 x 0.005 moles = 0.010 moles of acid needed to neutralise the antacid tablet.

  2. Neutralisation Investigation

    I predict that the higher the concentration of the acid solution, the greater the temperature change will be, and the greater the energy released. I have arranged to get sufficiently accurate and reliable results by using a burette to measure the quantities of solution, I will use polystyrene cups instead

  1. Aspirin Investigation

    Alternative Synthesis Routes for the Production of Aspirin Method One (Source: Organic Experiments (5th Edition) Louis F. Fieser and Ken Williamson) This method of obtaining aspirin demonstrates the effect of four acetylating catalysts: two bases, sodium acetate and pyridine; a Lewis acid, boron trifluoride; and a mineral acid, sulphuric acid.

  2. Rates of Reaction

    There is now more chance of a successful collision-taking place, as there are more particles that contain the activation energy needed to form products by breaking bonds and form new ones. As you can see from the graph on the left shows the relationship between concentration and time; it shows

  1. Free essay

    Chemistry investigation

    Here is a labelled diagram of what the experiment looked like: Results: Time (seconds) Result 1 (ml2) Result 2 (ml2) Result 3 (ml2) 10 20 30 40 50 60 Aim: To determine whether measuring the gas produced using a gas syringe is an accurate dependent variable when trying to find the rate of reaction.

  2. What effects the rate of a reaction

    The actual reason for the hydrogen to be produced is because Magnesium has two electrons in its outer shell. Hydrogen has just one electron overall and Chorine has seven electrons in its outer shell. When the reaction between the magnesium and the chorine and hydrogen which is together (Hydrochloric Acid)

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