Home
Class 12
CHEMISTRY
If half-life of a radioactive element is...

If half-life of a radioactive element is `3` hours. After `9` hours its activity becomes

A

`1//9`

B

`1//8`

C

`1//27`

D

`1//6`

Text Solution

Verified by Experts

The correct Answer is:
B
Cal. `N//N^(0)`
Promotional Banner

Topper's Solved these Questions

  • ATOMIC STRUCTURE AND RADIOACTIVITY

    RC MUKHERJEE|Exercise PROBLEMS (Answers bracketed with questions)|40 Videos

  • ATOMIC WEIGHT

    RC MUKHERJEE|Exercise PROBLEMS |6 Videos

Similar Questions

Explore conceptually related problems

If the half-life of a radioactive sample is 10 hours its mean life is

The half life of a radioactive element is 8 hours. A given number of nuclei of that element is reduced to 1//4 of that number after two hours.

The half life of a radioactive material is 6.93 hour. After how many hours will only one-twentieth of the material be left over? Take log_e (20) = 3.0.

The half-life of a radioactive nuclide is 20 hours. What fraction of original activity will remain after 40 hours?

The half life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be:

The half-life of a radioactive isotope is 3 hours. The value of its disintegration constant is

RC MUKHERJEE-ATOMIC STRUCTURE AND RADIOACTIVITY-Objective Problems
  1. The half-life of a radioisotope is 1.5 hours. If its initial mass is 3...

    Text Solution

    |

  2. The radioactivity due to C-14 isotope (half-life = 6000 years) of a sa...

    Text Solution

    |

  3. If half-life of a radioactive element is 3 hours. After 9 hours its ac...

    Text Solution

    |

  4. If 3//4 quantity of a radioactive element disintegrates in two hours, ...

    Text Solution

    |

  5. A sample of rock from moon contains equal number of atoms of uranium a...

    Text Solution

    |

  6. A radioactive isotope having a half life of 3 days was received after ...

    Text Solution

    |

  7. If N^(0) is the initial number of nuclei, number of nuclei remaining u...

    Text Solution

    |

  8. Radioactive material is deacign with t(1//2) = 30 days on being, separ...

    Text Solution

    |

  9. A radioactive substance has a constant activity of 2000 disintegration...

    Text Solution

    |

  10. The orbital angular momentum of an electron in2sorbital is

    Text Solution

    |

  11. For a d-electron, the orbital angular momentum is

    Text Solution

    |

  12. .(13)Al^(27) is a stable isotope. .(13)Al^(29) is expected to disinteg...

    Text Solution

    |

  13. Which of the following relates to photon both as wave motion and as a...

    Text Solution

    |

  14. The kinetic energy of an electron in the second Bohr orbit of a hydrog...

    Text Solution

    |

  15. Energy of an electron is given by E= -2.178 xx 10^(-18)J ((z^(2))/(n^(...

    Text Solution

    |

  16. The first ionisation potential of Na is 5.1eV. The value of electrons ...

    Text Solution

    |

  17. The correct set of four quantum numbers for valence electrons of rubid...

    Text Solution

    |

  18. Which of the following is the energy of a possible excited state of h...

    Text Solution

    |

  19. A stream of electrons from a heated filament was passed between two ch...

    Text Solution

    |

  20. Which of the following atoms has the highest first ionisation energy ?

    Text Solution

    |