Q18.The half-life of 198Au is 3 days. If atomic weight of 198Au is 198 g mol-1, then the activity of 2 mg of 198Au is [in disintegration second-1]: (1) 2 . 67 × 1012 (2) 6 . 06 × 1018 (3) 32 . 36 × 1012 (4) 16 . 18 × 1012
What This Question Tests
This question requires calculating the activity of a given mass of a radioactive isotope, involving its half-life, atomic weight, and Avogadro's number.
Concepts Tested
Formulas Used
A = λN
λ = ln2 / T_half
N = (mass/atomic weight) * N_A
📚 NCERT Sections This Tests
13.4 — Obtain Approximately The Ratio Of The Nuclear Radii Of The Gold Isotope
Physics Class 12 · Chapter 13
13.4 Obtain approximately the ratio of the nuclear radii of the gold isotope 197 79 Au and the silver isotope 10747 Ag .
13.2 — Obtain The Binding Energy Of The Nuclei 5626Fe And 20983 Bi In Units Of
Physics Class 12 · Chapter 13
13.2 Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units of MeV from the following data: m ( 5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
3.17 — During Nuclear Explosion, One Of The Products Is 90Sr With Half-Life Of
Chemistry Class 11 · Chapter 3
3.17 During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1mg of 90Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactivity and Activity
- Year
- 2021
- Shift
- 25 Jul Shift 1
- Q Number
- Q18
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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