1. Learner name:
Assessor name:
D Roczniak
Issue date:
13/11/17
Submission date:
30/11/17
Submitted on:
Programme:
NQF Applied science Level 3 Extended Diploma
Unit:
Unit 6: Investigative Project
Assignment reference and title:
Assignment 2: Project Planning

5. Step 1 – collect your equipment
Collect your safety equipment
Collect your equipment for your investigation
Set it up in front of you
Take a picture with your phone of your equipment

6. Step 2 – carry out and analysis
Carry out your investigation
Record your results in rough on page 3
Calculate a mean for your results
Read the information on graphs on page 4 and decide what type of graph you need to draw
Get some graph paper and draw a graph for your data

7. Draw appropriate graphs to help analyse the data to show differences and trends
Graph pointers
Independent variable at the bottom
Dependent variable at the side
Use the titles off your table to label your axis
Fill at least half a page of A4
Use a regular scale for both axis
Little ‘x’ to jot the point
Join each ‘x’ with a straight line
Do Not join it to ‘0’

8. Why use Standard Deviation?
Choose and carry out an appropriate statistical test. (Pass) Justify the choice of data analysis technique (merit)
Why use Standard Deviation?
It is a measure that is used to quantify the amount of variation or dispersion of a set of data values. A low standard deviation indicates that the data points tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values.

9. Practice Problem #1: Calculate the standard deviation of the following test data by hand. Use the chart below to record the steps. Test Scores: 22, 99, 102, 33, 57, 75, 100, 81, 62, 29 Step 1 – count the number of values - 10 Step 2 – calculate the mean = 66

10. Step 3 – calculate Remember: Mean = 66 22 99 10233 57 75 10081 62 29
-44 33 36
-33 -9
9 34 15 -4
-37
1936
1089
1296 81
1156
225 16
1369
8338

11. Step 4 – divide by the number of values: 8338 ÷ 10 = 833
Step 4 – divide by the number of values: 8338 ÷ 10 = You now have

12. Step 5 - Finally, find the square root of Square root of 8338 = 91
Step 5 - Finally, find the square root of Square root of 8338 = Step 6 – analyse: large s, therefore very spread data. Not very reliable.

13. Practice
The data set below gives the prices (in dollars) of cordless phones at an electronics store. 35, 50, 60, 60, 75, 65, 80

14. Comments on Accuracy
pH The true pH of catalase is pH 7. This should be the fastest time or the most oxygen gas collected. Do your results show this to be the case as well? If so that suggests some accuracy. If not it suggests some inaccuracies. Concentration As concentration increases the time taken for the paper disc to fall and rise should increase as there would be more successful collisions between enzyme and substrate. . Do your results show this to be the case as well? If so that suggests some accuracy. If not it suggests some inaccuracies.

15. Things which ensured accuracy
Taking volume readings at eye level
Reading from the meniscus
Using different syringes for each pH/concentration
Choosing the right size syringes to measure the volume – to reduce error in measuring.
Justification of method and equipment
State why your method choice ensured accuracy.
State why your equipment choice ensured accuracy.

16. Things which may affected accuracy
Oxygen dissolves in liquid so some oxygen may have dissolved and not been collected and measured/or accumulated on the disc to make it rise making the rise slower
Hydrogen peroxide would be broken down with each repeat affecting the concentration and therefore the reaction.
There may have been some contamination by using the same syringe for each pH or concentration of hydrogen peroxide as the same syringes were used.
The concentration of catalase in the potato/yeast/beetroot/liver was unknown.

17. Precision and Reliability
Look at your range bars – which is the largest and shows the least precision? Which the smallest and shows the most precision? Link these to reliability. e.g. The range bars at 0.5M are the largest with a range from 135 seconds to 95 seconds. This means the results are the least precise at this value and therefore are the least reliable.

18. Justifying choice of method in terms of reliability
How many repeats did you do? Why do you do more than one measurement for each value? What does this allow? What could you do to improve the reliability further should you do the experiment again?

19. Validity Did the method allow you to fully investigate the hypothesis?
Are your results accurate and reliable?
Restate here some experimental design issues or positives that would have affected your validity (you may have already mentioned them in you accuracy section).
Also consider the accuracy of equipment.