Q29.A radioactive nucleus (initial mass number A and atomic number Z) emits 3α-particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be (1) A−Z−8 (2) A−Z−4 Z−4 Z−8 (3) A−Z−12 (4) A−Z−4 Z−4 Z−2
What This Question Tests
This question tests the ability to track changes in mass number and atomic number through multiple steps of alpha and positron decay, and then calculate the final neutron-to-proton ratio.
Concepts Tested
Formulas Used
Alpha decay: (A, Z) → (A-4, Z-2)
Positron emission: (A, Z) → (A, Z-1)
Number of neutrons = A - Z
📚 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 .
13.5 — The Q Value Of A Nuclear Reaction A + B ® C + D Is Defined By
Physics Class 12 · Chapter 13
13.5 The Q value of a nuclear reaction A + b ® C + d is defined by Q = [ mA + mb – mC – md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic. (i) 11 H+13 H →12 H+12 H (ii) 126 C+126 C →1020 Ne+ 24 He Atomic masses are given to be m ( 12 H ) = 2.014102 u m ( 13 H) = 3.016049 u m ( 126 C ) = 12.000000 u m ( 1020 Ne ) = 19.992439 u
13.3 — A Given Coin Has A Mass Of 3.0 G. Calculate The Nuclear Energy That
Physics Class 12 · Chapter 13
13.3 A given coin has a mass of 3.0 g. Calculate the nuclear energy that would be required to separate all the neutrons and protons from each other. For simplicity assume that the coin is entirely made of 6329Cu atoms (of mass 62.92960 u).
📋 Question Details
- Chapter
- Nuclei
- Topic
- Radioactive Decay Series
- Year
- 2010
- Shift
- Unknown
- Q Number
- Q29
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 13: Nuclei
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