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

Chemistry: Practical Investigation

Extracts from this document...


Chemistry: Practical Investigation Aim To see how varying the concentration of hydrochloric acid affects its reaction time with calcium carbonate. CaCo3 + 2HCl CaCl2 + H2O + CO2 Apparatus In this experiment I will need: Hydrochloric acid, calcium carbonate, water, conical flask, a bung with hole for tube, burette, water basin, eye protection, stopwatch. Background science "A reaction rate is the speed at which reactants are converted into products in a chemical reaction. The reaction rate is given as the instantaneous rate of change for any reactant or product"1. Collision theory is the theory that atoms or molecules need to collide to react. Most, if not all, reactions also need activation energy for the reaction to occur, also orientation is needed. Factors affecting collision theory are surface area, catalysts, temperature and concentration. Surface area affects the rate of reaction because it increases the frequency of collisions as there is more to collide with, temperature affects the rate of reaction because it both increases the frequency of collisions and the energy in the collisions as it excites the atoms, while concentration affects the rate of reaction because it also increases the frequency of collisions as there are more atoms to collide into the calcium carbonate. ...read more.


Once done repeat the experiment using different concentrations of HCL (diluted with water) with ratios of acid: water as shown:- 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9. I decided on using a burette instead of a boiling tube or measuring cylinder because a burette is more precise and accurate, this is also the reason why I used a stopwatch instead of counting. Despite this they are not 100% accurate so some error margin in produced. Factors involved in this experiment include temperature, concentration and surface area. The factor I have decided to change is concentration. I will be able to change this factor by diluting the hydrochloric acid with water and I will keep the other factors the same by monitoring the temperature to keep it at a steady rate and by weighing the large chips of calcium carbonate each time so the experiment is fair. I use large chips because it is a slower reaction and so will leave less room for human error. I will use 10 different concentrations to increase the range of results and I will repeat the experiment three times for concentration to ensure any outliers can be found and discarded so to make sure that the data I will collect will be accurate and reliable, leading to a good quality of evidence on which to base my decision. ...read more.


Trends seen from the graphs show a positive correlation however it is not proportional meaning that the rate is affected greater at higher concentrations compared to lower concentrations and thus reaction gets faster towards the end, making the gradient progressively more. Conclusion From this experiment I can conclude that the concentration of an acid does have an effect on the rate of reaction because of collision theory. Evaluation Due to human and apparatus error then the concentration has ~0.05cm3 error, while the rate has an error of ~ 1 second and 0.5cm3 The results aren't proportional due to many factors. This experiment is exothermic and so the temperature increase may affect the results, also there is no way to get precisely the same surface area of calcium carbonate as they weren't pre-cut to specification. The level of confidence in the results is low because of the many outliers in the lines of best fit because of this the data is insufficient and unreliable. Ways in which I could improve the experiment and results would be to carve out calcium carbonate chips to a specific surface area, while using a cooler to effectively reduce the temperature increase caused by the thermal energy being transferred. ...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 Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Here's what a teacher thought of this essay

3 star(s)

This report is fairly well written, supported by some strong scientific theory. Specific strengths and improvements have been suggested throughout.

Marked by teacher Cornelia Bruce 17/04/2013

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 Patterns of Behaviour essays

  1. Find out how the rate of hydrolysis of an organic halogen compound depends on ...

    The lower the concentration, the slower the reaction. Eventually, the graph is horizontal: the gradient is zero, and the reaction has come to a stop. The rate of the reaction at the start is called the initial rate. The initial rate can be found by drawing a tangent to the

  2. Investigation into the factors that affect the enthalpy change during a displacement reaction.

    Reading were taken every 30 seconds starting from minute 0. After minute 3 the contents were stirred gently with a thermometer to unsure all the reactants had a chance to mix. Readings were taken up until minute 8 where the experiment was concluded.

  1. Rate of reaction of hydrochloric acid and mangesium ribbon.

    This was incorrect because it was not based on experimental evidence. Evaluation Was I precise in my measurements? I feel that I was precise and accurate in recording measurements. I measured the acid accurately by measuring the acid when the bottom of the liquid meniscus just touched the line on the measuring cylinder.

  2. How Does the Changing Temperature Affect the Rate of Fermentation by Yeast.

    I will ensure that I get precise measurements by using suitable equipment, like a balance for measuring the mass of yeast, and a small syringe for measuring the amount of glucose solution. I will read off the volume of gas from the measuring cylinder carefully to ensure accuracy.

  1. Physical and Chemical Properties/Changes of several household chemicals

    A 150mL beaker was placed below the funnel and the salt/sand/water mixture was poured into the funnel. The liquid that passed through was called the filtrate. d.) 10mL of the filtrate was poured into an evaporating dish. The dish was set on a square of wire gauze supported by an iron ring attached to the ring stand.

  2. To investigate the effect of varying the masses of white sugar and yeast and ...

    The 75,000mg of flour was then quantitatively added to the yeast/ white sugar solution and thoroughly mixed with a glass stirring rod until a semi-liquid dough or slurry was formed. This slurry was carefully poured into a 100ml measuring cylinder till it's top reached the 30ml mark.

  1. Investigating the effects of temperature on the rate of clotting milk and Rennet

    Enzymes can be used in both anabolism (the build up of simple chemicals into complex ones) and catabolism (the breakdown of complex chemicals into simpler ones). Enzymes are most commonly used in Catabolism, this particularly applies to animal digestive systems.

  2. An Investigation: Factors That Affect The Rate Of Reaction between Calcium carbonate and Hydrochloric ...

    The disadvantages of this method is that it is not an accurate way of recording how much gas is released as the balance may only notice small amounts of carbon dioxide in weight being let off by the reaction. Using a gas syringe would make a more precise reading of

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