Question

12. Calculate the activity in mCi and MBq of In-113 produced by irradiation of 1 g...

12. Calculate the activity in mCi and MBq of In-113 produced by irradiation of 1 g of pure Cd-111 for 3 hr with 12 MeV protons having a beam intensity of 1x10 13 particles/(cm 2 -sec). The cross section for formation of In-111 (T = 2.8 d) is 200 millibarns ( 1 mb = 1x10 -27 cm 2 ). Recall 1 mCi = 37 MBq

Homework Answers

Answer #1

12. Number of In-111 produced in 3 Hr is given by:

where, n is particles incedent per second per unit area, n = 1 x 1013 /cm2s

ns is number of source particles , ie. (1/111)x 6.022 x 1023 = 5.425 x 1021

sigma is crossection of formation = 200 x 10-3 x 10-24 cm2 (given incorrect in statement)

t is time of irradiation. t = 3 x 60 x 60 s = 10800 s

hence, number of In-2.8 atoms:

Half life of In-111 T1/2 = 2.8 days = 2.8 x 24 x 60 x 60 s

T1/2 = 241920 s

As radioactivity constant is given by:

/s

As initial activity is

Hence, we can write as:

and

as required

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT