Q17.The half-life of Au198 is 2. 7 days. The activity of 1. 50 mg of Au198 , if its atomic weight is 198 g mol−1 is, (NA = 6 × 1023 mol−1) (1) 240 Ci (2) 357 Ci (3) 535 Ci (4) 252 Ci JEE Main 2021 (16 Mar Shift 2) JEE Main Previous Year Paper
What This Question Tests
This question involves calculating the activity of a radioactive sample by first determining the number of nuclei from the given mass and then using the half-life to find the decay constant.
Concepts Tested
Formulas Used
T₁/₂ = ln2/λ
Activity = λN
N = (m/M)NA
📚 NCERT Sections This Tests
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.
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
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactivity and Activity
- Year
- 2021
- Shift
- 16 Mar Shift 2
- Q Number
- Q17
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
More from this Chapter
Q71.At a specific instant emission of radioactive compound is deflected in a magnetic field. The compound can emit (i) electrons (ii) protons (iii) He2+ (iv) neutrons The emission at instant can be (1) i, ii, iii (2) i, ii, iii, iv (3) iv (4) ii, iii
Q72.If N0 is the original mass of the substance of half- life period t1/2 = 5 years, then the amount of substance left after 15 years is (1) N0/8 (2) N0/16 (3) N0/2 (4) N0/4
Q73.If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should (1) increase (2) remain unchanged (3) decrease (4) first increase then decrease
Q82.In which of the folloiwng species the interatomic bond angle is 109∘28′? (1) NH3, (BF4)−1 (2) (NH4)+, BF3 (3) NH3, BF4 (4) (NH2)−1, BF3