6. Data Acquisition MATHEMATICS

Nuclear Particles

Word Problems on Nuclear Activities

I. Use R, the activities measured from Experiment 1 and Ro supplied by the manufacturer, to find approximately when the radioisotopes were manufactured, by substituting into the formula:

R = Roe- l t and solving for t, the elapsed time.

II. Find also the initial mass mo, of each radioisotope.

(Note: Set calculator to scientific mode fix 2)

 

1. Polonium Po-210 (alpha decay): Activity, Ro = 1/10 m Ci.

half-life, T1/2 = 138 days.

 

 

 

 

2. Thallium Tl-204 (beta decay): Activity, Ro = 1 m Ci.

half-life, T1/2 = 3.8 years.

  

 

 

 

3. Cobalt Co-60 (gamma decay): Activity, Ro = 1 m Ci.

half-life, T1/2 = 5.3 years

 

 

 

 

 

 

 

Word Problems on Nuclear Activities

 

II. Find m o, the initial mass of each source at the time it was manufacture.

1 u (atomic mass unit) = 1.67265E-24 g

1 mol (mole) = 6.002E23 u = 1 g of substance

1 Ci = 3.7E10 Bq (decays/sec)

 

1. Polonium Po-210 (alpha decay): Activity, Ro = 1/10 m Ci.

l (decay constant) = |-5.82E-8/sec| .

 

 

 

 

 

 

 
  1. Thallium Tl-204 (beta decay): Activity, Ro = 1 m Ci.

l (decay constant) = |-5.78E-9/sec |

 

 

 

 

 

 

 

 

3. Cobalt Co-60 (gamma decay): Activity, Ro = 1 m Ci.

l (decay constant) = |-4.15E-9/sec |