Two radioactive materials X₁ and X₂ have decay constants 5λ and λ respectively. If initially they have the same number of nuclei, then the ratio of number of nuclei of X₁ to that of X₂ […]
In a radioactive decay process, the negatively charged emitted β- particles are
Options
(a) the electrons produced as a result of the decay of neutrons inside the nucleus (b) the electrons produced as […]
The nuclei of which one of the following pairs of nuclei are isotones?
Options
(a) ₃₄Se⁷⁴,₃₁Ga⁷¹ (b) ₃₈Sr⁸⁴,₃₈Sr⁸⁶ (c) ₄₂Mo⁹²,₄₀Zr⁹² (d) ₂₀Ca⁴⁰,₁₆S³²
Correct Answer:
₃₄Se⁷⁴,₃₁Ga⁷¹
Explanation:
Isotones means number of neutron remains same.
The half life of radium is about 1600 year. Of 100 gram of radium existing now, 25g will remain unchanged after
Options
(a) 4800 year (b) 6400 year (c) 2400 year (d) 3200 year
In the reaction ₉₂U²³⁴→₈₇Y²²², how many α-particle and β-particles are emitted respectively?
Options
(a) 3,5 (b) 5,3 (c) 3,3 (d) 3,1
Correct Answer:
3,1
Explanation:
Change in A = 234 – 222 = 12
which of the following can not be emitted by radioactive substances during their decay?
Options
(a) Electrons (b) Protons (c) Neutrinos (d) Helium nuclei
Correct Answer:
Protons
Explanation:
No explanation available. Be the […]
A nucleus with mass number 220 initially at rest emits an α-particle. If the Q-value of the reaction is 5.5 MeV, calculate the kinetic energy of the α-particle
Options
(a) 4.4 MeV (b) […]
A nucleus of mass number 220, initially at rest, emits an α-particle. If the Q-value of the reaction is 5.5 MeV, then the energy of the emitted α-particle will be
Options
(a) 4.8 […]
Which of the following atoms has the lowest ionisation potential?
Options
(a) ₈O¹⁶ (b) ₇N¹⁴ (c) ₅₅Cs¹³³ (d) ₁₈Ar⁴⁰
Correct Answer:
₅₅Cs¹³³
Explanation:
No explanation available. Be the first to write the explanation […]
In which of the following systems will the radius of the first orbit (n=1) be minimum?
Options
(a) Single ionised helium (b) Deutron atom (c) Hydrogen atom (d) Doubly ionised lithium
Correct Answer:
Doubly […]
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