Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Periodic Table and Periodicity question

2015 · Shift 0 · Q21
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Chemistry
  4. /Periodic Table and Periodicity
  5. /2015 · Shift 0 · Q21

Periodic Table and Periodicity question

2015 · Shift 0 · Q21

JEE MainChemistryPeriodic Table and PeriodicityMCQ+4 / −1
The ionic radii (in Å) of N3−N_3^-N3−​, O2−O^{2-}O2− and F−F^-F− are respectively:
  1. A
    1.36, 1.71 and 1.40
  2. B
    1.71, 1.40 and 1.36
  3. C
    1.71, 1.36 and 1.40
  4. D
    1.36, 1.40 and 1.71
View written solutionFree

Correct answer: B

  1. Identify the species

    The ions are: N3−,O2−, and F−N^{3-},\\ O^{2-},\ \text{and}\ F^-N3−,O2−, and F−

    Each of these has 10 electrons, so they are isoelectronic with Ne.

  2. Rule for isoelectronic species

    In an isoelectronic series, ionic radius decreases as nuclear charge increases.

    Here, the nuclear charges are:

    • For N3−N^{3-}N3−: Z=7Z = 7Z=7
    • For O2−O^{2-}O2−: Z=8Z = 8Z=8
    • For F−F^{-}F−: Z=9Z = 9Z=9

    Since all have the same number of electrons, the ion with the smallest nuclear charge holds the electron cloud least tightly and hence has the largest radius.

    Therefore, N3−>O2−>F−N^{3-} > O^{2-} > F^-N3−>O2−>F−

  3. Match with given values

    The three radii given are 1.71,1.40,1.361.71, 1.40, 1.361.71,1.40,1.36 Å.

    According to the order above:

    • Largest radius 4ightarrow N^{3-} = 1.71\,\text{}
    • Next 4ightarrow O^{2-} = 1.40\,\text{}
    • Smallest 4ightarrow F^- = 1.36\,\text{}
  4. Check options

    • A: 1.36,1.71,1.401.36, 1.71, 1.401.36,1.71,1.40 wrong
    • B: 1.71,1.40,1.361.71, 1.40, 1.361.71,1.40,1.36 correct
    • C: 1.71,1.36,1.401.71, 1.36, 1.401.71,1.36,1.40 wrong
    • D: 1.36,1.40,1.711.36, 1.40, 1.711.36,1.40,1.71 wrong

Hence, the correct option is B.

PreviousNext

More from Periodic Table and Periodicity

  • The first ionization potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+ will be:2013 · MCQ
  • Which of the following represents the correct order of increasing first ionization enthalpy for Ca, Ba, S, Se and Ar?2013 · MCQ
  • The increasing order of the ionic radii of the given isoelectronic species is :2012 · MCQ
  • Outer electronic configuration of Gd (Atomic no : 64) is -2011 · MCQ
  • Which one of the following order represents the correct sequence of the increasing basic nature of the given oxides ?2011 · MCQ
  • The correct sequence which shows decreasing order of the ionic radii of the elements is2010 · MCQ
  • The set representing the correct order of ionic radius is :2009 · MCQ
  • In which of the following arrangements, the sequence is not strictly according to the property written against it2009 · MCQ