Investigating the half-life of Protactinium

Time / t (s) Average time for interval

0-10 5

12.5-22.5 17.5

25-35 30

37.5-47.5 42.5

50-60 55

62.5-72.5 67.5

75-85 80

87.5-97.5 92.5

100-110 105

112.5-122.5 117.5

125-135 130

137.5-147.5 142.5

150-160 155

162.5-172.5 167.5

180

192.5

205

217.5

230

242.5

255

267.5

To get the 10 seconds minus the background count I subtracted 6 counts from the amount of coutns in 10 seconds. Example: Counts per 10 seconds- 6 = Counts per 10 seconds minus the background counts

What to do:

What to do: 1. Process your data by completing the table above. 2. Write example calculations in the space below for all the calculations you have to used in 1 above.To get the 10 seconds - the background count i subtracted 6 counts from the amounts of counts in 10 seconds. Example: Counts per 10 seconds - 6 equals counts pero 10 seconds 3. Use Excel to plot a graph of Activity (Y axis) against time (Xdata and show the equation on your graph. 4. Use the graph to find the half-life of Protactinium.Lets take, time: 20 that is about 4.6 of activity, so we half 20 it equals time: 10, and about 9.6 of activity. Now we do 9.which equals to 5 of activity. Which in conlclusion 5 should be the half time of Protactium. 5. "The half-life of the radioactive sample does not change with time". Use your graph to provide evidence to support this statement. Because as the graph as curved line, almost a perfect curved line the graph will always will give the same results, 5 of halftime, where ever we measure. 6. Submit your work via Turnitin. 7. Present your completed work on your blog in a siutable format.

Background count rate 6 counts in 10 seconds

Counts in 10 seconds Counts per 10 seconds minus

background count

292 286

253 247

219 213

183 177

184 178

154 148

144 138

109 103

112 106

98 92

107 101

70 64

69 63

48 42

54 48

43 37

53 47

44 38

46 40

27 21

22 16

22 16

To get the 10 seconds minus the background count I subtracted 6 counts from the amount of coutns in 10 seconds. Example: Counts per 10 seconds- 6 = Counts per 10 seconds minus the background counts

the table above.

2. Write example calculations in the space below for all the calculations you have to used in 1 above.the background count i subtracted 6 counts from the amounts of counts in 10 seconds. Example: 6 equals counts pero 10 seconds - the background counts.

3. Use Excel to plot a graph of Activity (Y axis) against time (X axis) for Protactinium. Add a best fit logarithmic line to your

life of Protactinium. Lets take, time: 20 that is about 4.6 of activity, so we half 20 it equals time: 10, and about 9.6 of activity. Now we do 9.which equals to 5 of activity. Which in conlclusion 5 should be the half time of Protactium.

life of the radioactive sample does not change with time". Use your graph to provide evidence to support this

Because as the graph as curved line, almost a perfect curved line the graph will always will give the same results, 5 of half

your completed work on your blog in a siutable format.

Activity (counts per second) A

/ Bq

28.6

24.7

21.3

17.7

17.8

14.8

13.8

10.3

10.6

9.2

10.1

6.4

6.3

4.2

4.8

3.7

4.7

3.8

4

2.1

1.6

1.6

To get the 10 seconds minus the background count I subtracted 6 counts from the amount of coutns in 10 seconds. Example: Counts per 10 seconds- 6 = Counts per 10 seconds minus the background counts

0

5

10

15

20

25

30

35

0 5

TIM

E

2. Write example calculations in the space below for all the calculations you have to used in 1 above. the background count i subtracted 6 counts from the amounts of counts in 10 seconds. Example:

for Protactinium. Add a best fit logarithmic line to your

Lets take, time: 20 that is about 4.6 of activity, so we half 20 it equals time: 10, and about 9.6 of activity. Now we do 9.6-4.6

life of the radioactive sample does not change with time". Use your graph to provide evidence to support this

Because as the graph as curved line, almost a perfect curved line the graph will always will give the same results, 5 of half

y = 32.79e

5 10 15 20 25

Activity

Activity (counts per second) A / Bq

Activity (counts per second)A / Bq

Expon. (Activity (counts persecond) A / Bq)

y = 32.79e-0.13x

Activity (counts per second)

Expon. (Activity (counts persecond) A / Bq)