Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  • Level: GCSE
  • Subject: Science
  • Essay length: 2279 words

Investigation into the effect of concentration on the rate of reaction between calcium carbonate and hydrochloric acid

Extracts from this essay...

Introduction

Investigation into the effect of concentration on the rate of reaction between calcium carbonate and hydrochloric acid. Introduction Equation: Calcium carbonate + hydrochloric acid carbon dioxide + water + calcium chloride CaCO + HCl CO + H O + CaCl During this reaction Carbon dioxide is formed. We measured the rate of reaction by collecting the Carbon dioxide in a gas syringe and timing how long it takes to collect 30cm of gas in the gas syringe. Variables that Affect the Rate of Reaction: -Concentration- if there is a higher concentration of acid then there will be a faster rate of reaction because there will be more reactant particles per unit volume, so there will therefore be more successful collisions occurring. -Temperature- if the temperature is higher there will be a faster reaction rate. This is because the average kinetic energy of the particles will be higher and therefore the collisions will have more energy so successful collisions will increase. -Size of chips (surface area)- If the marble chips are larger then there will be more surface area exposed and so there will be a faster reaction rate due to more successful collisions occurring. -Catalyst- A catalyst lowers the energy needed for successful collisions. So the reaction rate will therefore be faster.

Middle

If the concentration is higher then there will be more particles per unit volume. Observations The only possible anomaly that I can see from the preliminary results table is the result for time taken to collect 30cm of gas, and the concentration of acid being 12. Results for actual experiment. Concentration of solution moles dm 3 Volume of Acid moles dm 3 (cm ) Volume of Water (cm ) Time taken to collect 30cm of gas (s) (1st test) Time taken to collect 30cm of gas (s) (2nd test) Time taken to collect 30cm of gas (s) (3rd test) Average time taken to collect 30cm of gas (s) 2.0 20 0 6 7 8 07.00 1.8 18 2 9 9 10 09.33 1.6 16 4 11 10 10 10.33 1.4 14 6 13 12 11 12.00 1.2 12 8 15 10 14 13.00 1.0 10 10 18 17 19 18.00 Rate of reaction: 1/time Concentration of solution moles dm 3 Rate of reaction s 1 2.0 0.14 1.8 0.11 1.6 0.10 1.4 0.08 1.2 0.08 1.0 0.06 Analysing I have found from my results that my prediction was correct and that as the concentration of acid increases, the rate of reaction increases, and as the concentration of acid decreases, the rate of reaction decreases.

Conclusion

There are still some factors that could cause an anomaly using this method, for example, human error. Reactions could be delayed when starting the stop clock. Other anomalies could have been because the gas syringe could have stuck, also, even though we did our best to keep the chips the same size, we could not guarantee they would be the correct size. This would alter the rate of reaction to make it faster or slower. We could possibly have ruled this out by getting a machine to cut the marble chips into precise sizes, but this would take a long time and would be impractical, and is therefore beyond our control. The temperature could also have changed, even though we attempted to keep it the same, although we did not measure the temperature with a thermometer. This was also beyond our control as we did not have the equipment to keep the temperature at a constant level. Another problem that we found was that one of the boiling tubes broke during the experiment and a small bit of glass had fallen out of the bottom of it. This was faulty equipment. Other than these possible reasons I can conclude that the experiment as fairly and accurately as possible with the equipment and conditions that we were operating in, and that the results are valid. ?? ?? ?? ?? Charlotte Bell 10A

The above preview is unformatted text

Found what you're looking for?

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

Not the one? Search for your essay title...
  • Over 180,000 student essays
  • Every subject and level covered
  • Thousands of essays marked by teachers
  • Over 180,000 essays
    written by students
  • Annotated by
    experienced teachers
  • Ideas and feedback to write
    your own great essays

Marked by a teacher

This essay has been marked by one of our great teachers. You can read the full teachers notes when you download the essay.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the essay page.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review under the essay preview on this page.