Chemical Economics Investigation: - speeding up the reaction speed between calcuim carbonate and hydrochloric acid.

Before I could start the experiment I had to predict how much hydrochloric acid is was going to use and how much calcuim carbonate I needed, you can see how I did this by looking at the equation below: -

* I have to remember that 1 mole of any gas occupies 24,000cm cubed at room

temperature and pressure.

Word equation

Calcium carbonate

+

Hydrochloric acid

Calcuim chloride

+

Water

+

Carbon dioxide

Balanced equation

CaCO3

+

2Hcl

CaCl2

+

H2O

+

Co2

Relative formula masses

40+12+16+16+16

2*(1+35.5)

40+35.5+35.5

+1+16

2+16+16

Relative formula masses added up

00

73

11

8

44

Equation for mass of calcium carbonate

00/2400*100=0.4

Equation for volume of hydrochloric acid

00/2400*1000=4.16/4.2

Method

) Take a gas syringe fixer to a clamp stand, conical flask, a measuring cylinder, hydrochloric acid solution, calcuim carbonate crystals, a set of scales, Bunsen burner, heat proof mat, gauze, a tri-pod, a thermometer and a stop-watch.

2) Measure out how much hydrochloric acid solution you need in the measuring cylinder and how much calcuim carbonate crystals you need to use. Put the hydrochloric acid into the conical flask and then place it on the gauze and turn on the Bunsen burner and heat it up to the temperature you want to start at.

3) Place the crystals into the conical flask when you have heated the hydrochloric acid to the temp you want. Attach the gas syringe to the conical flask and then read off the amount of gas produced every 10seconds for a minute.

4) Repeat the above for a range of different temperatures and do repeats for each temp so you can get a good average.

5) Wear an apron and goggles at all times as substances can be harmful, remember to write all results into a table.

Results table

Volume of gas (cm3) after every 10 seconds

Temperature (*c)

0

0

20

30

40

50

60

Room temp (24)

0

5

25

30

33

36

40

30

0

20

28

35

40

44

46

40

0

24

34

40

45

49

53

50

0

23

42

47

50

53

56

60

0

46

65

84

00

Conclusion

By looking at my graphs that I have produced I can see a very clear patter, has you in the temperature the speed of the reaction increases. Although I did produce a good set of results I did have problem getting the experiment to work as quick as it should have. I predicted that I needed to use 4.2g of calcium carbonate and 0.4cm3 of hydrochloric acid. When I went to use these amounts I found that they were reacting very slow and it would not have giving efficient enough results, so I had to times each of the reactants by 4 to make it 4 times greater, so instead of 0.4g of calcium carbonate I would have to use 1.6g and instead of using 4.2cm3 of hydrochloric acid I would have to use 16.8cm3. By doing this it gave me more accurate and efficient results. There was another point that let my results down is that I didn't collect enough data to produce averages.

The speed of the reaction increases as the temperature of the hydrochloric acid increased, this because when you heat up the solution the particles become more active and start to move/ vibrate faster, by the particles being in this fast motion their will be more collisions between the calcium carbonate and the hydrochloric acid particles speeding up the rate of the reaction.

Evaluation

I think the experiment that I have just completed was quit fair but not fair enough to be exact because there may have been some hydrochloric lost because I might not have got it all out of the measuring cylinder and I did not have enough time to do repeats and get averages so that was a main limitation for me. I think all my measurements that I made were accurate and I kept all of my key variables under control. I did get some odd results that did not fit my line of best fit, that was because I did do repeats to get an average which would have mad my results more accurate. I could have improved the experiment that I did by having more time to do it in so I could get repeats because I fell I was very rushed for time.