Home
Class 10
CHEMISTRY
Assertion (A): The first period in perio...

Assertion (A): The first period in periodic table contain only two elements. Reason (R) : 'K' subshell could be occupied by two electrons only, `1s^1`and `1s^2`.

A

Both 'A and 'R' are correct and 'R' is correct explanation of 'A'

B

Both 'A and 'R' are correct and 'R' is not correct explanation of 'A'

C

A' is correct but 'R' is wrong

D

A' is wrong but 'R' is correct

Text Solution

Verified by Experts

Promotional Banner

Topper's Solved these Questions

  • CLASSIFICATION OF ELEMENTS -THE PERIODIC TABLE

    VGS PUBLICATION-BRILLIANT|Exercise CREATIVE QUESTIONS FOR NEW MODEL EXAMINATION (SECTION -IV) (APPLICATION TO DAILY LIFE , CONCERN TO BIODIVERSITY )|4 Videos

  • CLASSIFICATION OF ELEMENTS-THE PPERIIODIC TABLE

    VGS PUBLICATION-BRILLIANT|Exercise EXERCISE|20 Videos

Similar Questions

Explore conceptually related problems

1st period contains……….elements.

Assertion (A): ‘H' & 'He' belongs to period - 1. Reason (R) : 'H & 'He' contain only one main shell 'K'.

Use the periodic table to identify elements (a) With 5 electrons in the outer subshell (b) Would tend to lose two electrons (c) Would tend to gain two electrons

Use the periodic table to identify elements. (b) Would tend to lose two electrons.

Use the periodic table to identify elements. (c ) Would tend to gain two electrons.

Assertion (A) : The orbital angular momentum of 2s-electron is equal to that of 3s-electron. Reason (R) : The orbital angular momentum is given by the relation sqrt(l(l+1))(h)/(2pi) and the value of 1 is same for 2s-electron and 3s-electron.

1s^2 2s^2 is the electronic configuration of which element?

Assertion (A) : _4Be does not form covalent bonds. Reason (R): Electronic configuration of Be is 1s^2 2s^2 and it has no unpaired electrons.

VGS PUBLICATION-BRILLIANT-CLASSIFICATION OF ELEMENTS-THE PERIODIC TABLES-EXERCISE
  1. Pavan (P) : The general electronic configuration of alkali metal famil...

    Text Solution

    |

  2. Assertion (A): ‘H' & 'He' belongs to period - 1. Reason (R) : 'H & 'He...

    Text Solution

    |

  3. Assertion (A): The first period in periodic table contain only two ele...

    Text Solution

    |

  4. Suneetha (A) : Third period contain 18 elements, because it has 3 subs...

    Text Solution

    |

  5. James (A) : The positive ions of an element has less in size than its ...

    Text Solution

    |

  6. Balu (B) : Valence of an element with  respect to hydrogen is the numb...

    Text Solution

    |

  7. Valeney of Ca is

    Text Solution

    |

  8. Assertion (A) : Atomic radii increase from top to bottom in a group of...

    Text Solution

    |

  9. Assertion (A): Atomic radii of elements decrease across a period from ...

    Text Solution

    |

  10. Assertion (A) : The size of Na^+ ion is less than 'Na' atom. Reason (R...

    Text Solution

    |

  11. It is easier to remove one electron from O than N because Nitrogen has

    Text Solution

    |

  12. Which of the following property decreases down a group :

    Text Solution

    |

  13. Actinides belongs to period.

    Text Solution

    |

  14. Ionization energy is not depending on

    Text Solution

    |

  15. Moseley calculated the number of positive charges in the atoms by anal...

    Text Solution

    |

  16. Group 13(IIIA) elements are known as

    Text Solution

    |

  17. The incompletely filled period is

    Text Solution

    |

  18. The inner transition elements are elements.

    Text Solution

    |

  19. Ionization energy increases with the Increase of

    Text Solution

    |

  20. Number of essential elements are

    Text Solution

    |