Metal Carbonate Controlled Assessment
Controlled Assessment Task:
State the hypothesis you will be testing in your investigation:
The speed of a metal carbonate breaking down depends on where the metal is in the reactivity series. The more reactive a metal is the slower it takes for it to breakdown. The less reactive a metal is it breaks down faster.
Explain the hypothesis using scientific ideas:
The metal carbonate which is lower in the reactivity series such as copper can thermally decompose much faster because it is the least reactive metal so its an unstable carbonate and the bonds are much weaker. So the metal that is much higher in the reactivity series such as calcium, is more thermally stable and hard to decompose also the more reactive the metal is it forms …show more content…
the most stable carbonates. Also calcium carbonate have more of a stronger bong with their molecules and due to this it takes really long for limewater to turn milky.
Equipment:
• Bunsen burner: This is needed to heat the metal carbonate
• 16 boiling tubes: 4 boiling tubes needed for one carbonate because it includes repetition.
Four carbonates altogether so 16 boiling tubes.
• Heat proof mat- For the bunsen burner to be placed on top of it to avoid accidents
• Two clamps- One clamp to hold the metal carbonate and one to hold the limewater.
• Scale- To equally measure all the carbonates you heat.
• Stop watch: To check the time it took for the metal carbonate to turn the limewater milky.
• Measuring cylinder: To know how much limewater needed to put into the boiling tube.
• Rubber bung- So it can go inside the boiling tube with the carbonate in.
• Delivery tube: So the Co2 is collected in the limewater.
• Eye protection- To protect the eyes from spills.
• Splinter- To light the bunsen burner.
Controls:
• I will have the same mass of the different types of metal carbonates. To control this I will weigh the carbonates and make sure its the same mass for each time when we heat it.
• I will be changing the metal carbonates and I will control this by making sure I have weighed the same mass of metal …show more content…
carbonate.
• Also what I will keep the same is the maximum time to heat the metal carbonate for the limewater to turn milky which is two minutes. If it does not turn milky by two minutes then I will control it by turning the bunsen burner off and have keeping an eye on the stop watch.
• A variable which will be changed is the limewater after the metal carbonate has been burnt. To control this I will always measure the limewater in a measuring cylinder making sure it is the same amount every time.
• Also I will keep the same distance of the bunsen burner and boiling to tube the same. To control this I will have ruler with me and I will measure the same distance for each time I burn the metal carbonates.
Risks
• In case a spill or a splash happens while doing the experiment having eye protection on manages the risk.
• Also when not using the bunsen burner put on the yellow flame (safety flame) so it is visible so people can see it and it decreases the risk of being burnt.
• Make sure hair is tied back. If hair touches the bunsen burner then the whole head will be burnt.
• The delivery tube should be pulled of out of the tube before turning the bunsen burner off to avoid suck back
Method
1) Put on your goggles
2) Take the metal carbonate to the scale to find out the mass. It should read two grams and then put the carbonate in the boiling tube.
3) Place the bunsen burner on a heat proof mat.
4) Measure 25cm2 of limewater in a measuring cylinder.
5) Fit one clamp stand with the boiling tube which has the metal carbonate with the delivery tube inside of the boiling tube.
Ensure that the metal carbonate is slanted side ways and about the bunsen burner. Measure with a ruler the distance it should be 15cm.
6) With another clamp , screw on another boiling tube.
7) Fill the tube with limewater
8) The delivery tube then should go into the limewater
9) Mark a X on the boiling tube filled with limewater
10) Make sure that the stop watch is ready and working and on 0 seconds.
11) Get a light splint and light the bunsen burner.
12) When bunsen burner is lit that it when the stopwatch it turned on.
13) When limewater is turned milky enough that you cannot see the X stop the stopwatch. If limewater has not turned milky by two minutes stop the timer.
14) Before turning the bunsen burner of make sure you take out the delivery tube from the limewater to avoid suck back.
15) Then turn of the bunsen burner
16) Note down on results table the time it took for the limewater to turn milky.
17) Repeat the experiment with the other metal carbonates.
Secondary evidence - comment on the quality of this secondary
evidence
I used the class results to compare my results which leaded into improving reliability. The results were taken from 5 different groups in my classroom. As shown on the results below the average taken from the five groups in my class are much more reliable than the data me and my lab partner collected provided that the same method was carried out.
Part C: Conclusions:
State how you are going to present the results you have collected.
I am going to present my results in bar charts as the independent variables are categorical.
Present you processed results on a separate piece of paper and hand it in with your workbook
(Handed in)
Quality of evidence - State how identified and dealt with any anomalies from your primary and secondary evidence:
The quality of my primary evidence was good there was no anomalies. However quality of secondary evidence was fair. Even though it had a sample size of five groups which made it more reliable not all the groups had enough time to do all the carbonates so it was not really fair. There were also three anomalies as you can see on table two. Magnesium carbonate on the 2nd reading had two outliers and there was another one in calcium carbonate. I dealt them by discarded them in my overall average.
Conclusion based on evidence
Looking at my primary evidence and table three, I can conclude that the more reactive a metal is the more slow it took for the metal carbonate to decompose . So my hypothesis was right. However this conclusion does not correspond with my secondary evidence , because according to the secondary evidence copper carbonate was slower to decompose then Zinc. However Zinc is more reactive than copper but the average in secondary evidence concludes that copper carbonate was slower to decompose.
State the hypothesis you will be testing in your investigation:
The speed of a metal carbonate breaking down depends on where the metal is in the reactivity series. The more reactive a metal is the slower it takes for it to breakdown. The less reactive a metal is it breaks down faster.
Explain the hypothesis using scientific ideas:
The metal carbonate which is lower in the reactivity series such as copper can thermally decompose much faster because it is the least reactive metal so its an unstable carbonate and the bonds are much weaker. So the metal that is much higher in the reactivity series such as calcium, is more thermally stable and hard to decompose also the more reactive the metal is it forms …show more content…
the most stable carbonates. Also calcium carbonate have more of a stronger bong with their molecules and due to this it takes really long for limewater to turn milky.
Equipment:
• Bunsen burner: This is needed to heat the metal carbonate
• 16 boiling tubes: 4 boiling tubes needed for one carbonate because it includes repetition.
Four carbonates altogether so 16 boiling tubes.
• Heat proof mat- For the bunsen burner to be placed on top of it to avoid accidents
• Two clamps- One clamp to hold the metal carbonate and one to hold the limewater.
• Scale- To equally measure all the carbonates you heat.
• Stop watch: To check the time it took for the metal carbonate to turn the limewater milky.
• Measuring cylinder: To know how much limewater needed to put into the boiling tube.
• Rubber bung- So it can go inside the boiling tube with the carbonate in.
• Delivery tube: So the Co2 is collected in the limewater.
• Eye protection- To protect the eyes from spills.
• Splinter- To light the bunsen burner.
Controls:
• I will have the same mass of the different types of metal carbonates. To control this I will weigh the carbonates and make sure its the same mass for each time when we heat it.
• I will be changing the metal carbonates and I will control this by making sure I have weighed the same mass of metal …show more content…
carbonate.
• Also what I will keep the same is the maximum time to heat the metal carbonate for the limewater to turn milky which is two minutes. If it does not turn milky by two minutes then I will control it by turning the bunsen burner off and have keeping an eye on the stop watch.
• A variable which will be changed is the limewater after the metal carbonate has been burnt. To control this I will always measure the limewater in a measuring cylinder making sure it is the same amount every time.
• Also I will keep the same distance of the bunsen burner and boiling to tube the same. To control this I will have ruler with me and I will measure the same distance for each time I burn the metal carbonates.
Risks
• In case a spill or a splash happens while doing the experiment having eye protection on manages the risk.
• Also when not using the bunsen burner put on the yellow flame (safety flame) so it is visible so people can see it and it decreases the risk of being burnt.
• Make sure hair is tied back. If hair touches the bunsen burner then the whole head will be burnt.
• The delivery tube should be pulled of out of the tube before turning the bunsen burner off to avoid suck back
Method
1) Put on your goggles
2) Take the metal carbonate to the scale to find out the mass. It should read two grams and then put the carbonate in the boiling tube.
3) Place the bunsen burner on a heat proof mat.
4) Measure 25cm2 of limewater in a measuring cylinder.
5) Fit one clamp stand with the boiling tube which has the metal carbonate with the delivery tube inside of the boiling tube.
Ensure that the metal carbonate is slanted side ways and about the bunsen burner. Measure with a ruler the distance it should be 15cm.
6) With another clamp , screw on another boiling tube.
7) Fill the tube with limewater
8) The delivery tube then should go into the limewater
9) Mark a X on the boiling tube filled with limewater
10) Make sure that the stop watch is ready and working and on 0 seconds.
11) Get a light splint and light the bunsen burner.
12) When bunsen burner is lit that it when the stopwatch it turned on.
13) When limewater is turned milky enough that you cannot see the X stop the stopwatch. If limewater has not turned milky by two minutes stop the timer.
14) Before turning the bunsen burner of make sure you take out the delivery tube from the limewater to avoid suck back.
15) Then turn of the bunsen burner
16) Note down on results table the time it took for the limewater to turn milky.
17) Repeat the experiment with the other metal carbonates.
Secondary evidence - comment on the quality of this secondary
evidence
I used the class results to compare my results which leaded into improving reliability. The results were taken from 5 different groups in my classroom. As shown on the results below the average taken from the five groups in my class are much more reliable than the data me and my lab partner collected provided that the same method was carried out.
Part C: Conclusions:
State how you are going to present the results you have collected.
I am going to present my results in bar charts as the independent variables are categorical.
Present you processed results on a separate piece of paper and hand it in with your workbook
(Handed in)
Quality of evidence - State how identified and dealt with any anomalies from your primary and secondary evidence:
The quality of my primary evidence was good there was no anomalies. However quality of secondary evidence was fair. Even though it had a sample size of five groups which made it more reliable not all the groups had enough time to do all the carbonates so it was not really fair. There were also three anomalies as you can see on table two. Magnesium carbonate on the 2nd reading had two outliers and there was another one in calcium carbonate. I dealt them by discarded them in my overall average.
Conclusion based on evidence
Looking at my primary evidence and table three, I can conclude that the more reactive a metal is the more slow it took for the metal carbonate to decompose . So my hypothesis was right. However this conclusion does not correspond with my secondary evidence , because according to the secondary evidence copper carbonate was slower to decompose then Zinc. However Zinc is more reactive than copper but the average in secondary evidence concludes that copper carbonate was slower to decompose.