Through further calculations I have ound out that the average energy release per gram of CaC12 is 224. 96]. I also found out, thank to my gradient, that the average temperature rise per gram is 2. 14 which is expected. If you check my research then you can see that these figures are slightly similar to them however are not exactly the same due to a reason which I will explain later on. Whilst going through my results I came across an anomaly which was not included when making the graph or taking an average. The anomaly can be located in the results table.
The anomaly was in the third attempt for the final experiment hich was when we added 5g of calcium chloride. This was an anomaly as it matched none of our previous result due to it being too high. We dealt with this by not including it in the averages or when finding out the energy transfers because it would then provide us with inaccurate results. I believe that we encountered an anomaly because of the fact that it was the last experiment so we were in a rush to get out of school and we may have rushed this final experiment thereby causing this anomaly.
The line that was shown on the graph was proportionally steep as it was a erfect straight line showing that the mass of calcium chloride is directly proportional to the temperature rise. So from this we can also infer that the mass of calcium chloride is directly proportional to the energy released. 3) Compare results of your own investigation(Part 2) with the data from other groups and any information you collected In your research(Part 1) We have compared our results with two different groups. After looking at both groups I have realised that they both show the same pattern/trend as mine.
Both of the groups have shown a directly proportional relationship. While comparing the results I compared the verage rise In temperature they reached for each gram and then our average rise In temperature. Our average rise In temperature for 1 gram was 2. 930C and both of the groups got similar results with 2. 03 and 2. 6. Even though there Is a difference In the numbers the difference is not very large. In fact It Is the exact opposite, It Is very small. I went on to compare all of the results from our tables and see if they were reproducibility of my experiment is very high.
This also shows that the trend I found is correct as not Just one group but two different groups got results that show the same trend as mine. Furthermore when I compare the results I received to my research I collected in Part 1, I have some strange findings. In my research I found out the energy release per gram of anhydrate calcium chloride was 737] per gram. However I did not receive this result. In fact I got much less. My result was As you can see this is nowhere near the 737 grams it should. I have however found reasons for why this may have occurred.
You see the result I got in Part 1 was from an experiment done with much more precision than ours and under much more controlled conditions. So the calcium chloride we were using was not from a fresh atch so it had already reacted with the air before we started using it. Therefore our results could have been affected by this and that could explain the difference in energy transfer per gram. 4) Evaluate your results, the methods you used and how well you managed the risks 5) Do your results from Part 2 support the hypothesis you suggested?
Explain your answer. My results definitely do support the predictions I made in my hypothesis. Within my hypothesis I predicted that when we increase the amount of calcium chloride we put in to the water the temperature change will also increase and therefore there will be ore energy released. My results as you can see if you have a look at them show exactly this. My results showed that as we increase the amount of CaC12, the temperature change increased and this meant that the energy released was also increased.
I was able to predict this as I knew that the experiment we were going to carry out was going to be an exothermic reaction which involved breaking and making of bonds. I also knew that theoretically if you double the amount of CaC12 then you will be making double the amount of bonds and therefore there will be more energy released. This all allowed me to be able to predict the pattern of my esults for the experiment we carried out. 6) In their instant coffee drink, the “Instant Food Company’ wants to be able to heat 100cm3 of water from 200C to 700C.
Use the results of your investigation (Part 2) to suggest how much calcium chloride they would need to use per can. How does this compare to data and information that you have found in your research (Part 1) Why do you think there are differences between these findings? Use relevant scientific explanations in your answer and show your working for any calculations In order to work this out we must firstly know how much energy will be released as ou must use the formula for energy released. After substituting in the relevant numbers I get the result 21000].
Energy released 0) =100g (mass of water) x4. 2 (Specific heat capacity of water) x500C (Change in temperature) Now that I know how much energy is released in this reaction I can work out how much CaC12 they will require by using the results from my experiment. If you look at my results table you can see that 1 gram of Calcium Chloride will release an average of 224. 9] so in order to work out how many grams will release 21000], I will have to use this number and divide it by 21000. 21000/224. 6=93. 35 So now that I know that they will require 93. 5g of CaC12 and then they will be able to heat the water from 200C to 700C. I have gotten to this by using the results I got from the experiment, however as I have already mentioned these results when compared to my research from Part 1 seems to not be as accurate. I have explained that the reason for the difference in my findings could be due to the fact that the calcium chloride we have used was not 100% anhydrate as some of it had already reacted with the air and therefore the results I achieved were nowhere near what my research showed.
In my opinion it would probably be wiser to use the results from the research as this would probably provide them with a more accurate answer. So we would have to follow the same steps and find out how much 1 gram releases and then divide that by 21000]. According to my research from Part 1, 1 gram of CaC12 will release approximately 737]. So we now do 21000/737 to find out how many grams of CaC12 will be required to release 21000 J so that we get the temperature to rise by 500C. 21000/737=28. 49 So Instant Food Company will most likely require 28. 49g of CaC12 in order to make the temperature rise by 500C from 200C to 700C.