Please wait...

Periodic Properties Test - 5
Result
Periodic Properties Test - 5
  • /

    Score
  • -

    Rank
Time Taken: -
  • Question 1/10
    1 / -0

    In any period, the valency of an element with respect to oxygen

    Solutions

    The valency first increases from 1 to 4 (IA to VIA) and then, decreases from a (4 to 1) VA to VII A.

     

  • Question 2/10
    1 / -0

    In which of the following arrangements is the order NOT according to the property indicated against it?

    Solutions

    B < C < N < O is not the correct increasing order of of the first ionization energies.
    Although the ionization energies increase across the period, but the ionization energy of nitrogen is more than that of oxygen. This is because of the stable configuration of half filled p-orbitals in nitrogen.

     

  • Question 3/10
    1 / -0

    Which of the following has the largest size?

    Solutions

    A cation is always smaller than the parent atom. Therefore, size of Al will be larger than that of its ion.

     

  • Question 4/10
    1 / -0

    Which of the following statements is correct?

    Solutions

    Anions are always larger than their parent atoms and also, than their cations.

     

  • Question 5/10
    1 / -0

    Among the elements of period III, the atomic size is the maximum for

    Solutions

    On moving across the period the effective nuclear charge increases and consequently the atomic radius decreases.
    Alkali metals have the largest value of atomic radius in their respective periods.
    The elements of period III are: Na, Mg, Al, Si, P, S, Cl, Ar
    Hence, sodium has the largest atomic radius in period III.

     

  • Question 6/10
    1 / -0

    Which of the following arrangements represents the correct order of electron gain enthalpies (with negative sign) of the given atomic species?

    Solutions

    The negative value of electron gain enthalpy increases across the period and decreases down the group.
    However, oxygen and fluorine have lesser negative value of electron gain enthalpies than sulphur and chlorine, respectively because of the small atomic radii of these elements, which leads to repulsions in the gain of electrons.

     

     

  • Question 7/10
    1 / -0

    The correct order of ionisation energies is

    Solutions

    Ionisation energy increases with increase in the penetration power of the orbitals as the ionization energy is higher for the electron which is closer to the nucleus and experiences a stronger nuclear pull.
    s-orbital,owing to its spherical shape has the maximum penetration followed by p, d and f orbitals
    Hence the order of the ionization energies of the orbitals is the same as the penetration power of the orbitals.
    s > p > d > f

     

  • Question 8/10
    1 / -0

    The first, second and third ionisation energies of an atom are 737, 1451 and 7733 kJ mol-1, respectively. The element can be

    Solutions

    The third ionisation potential is much larger than the second. It implies that the element aquires a noble gas configuration after the loss of two electrons.
    Hence, the element can be Mg.

     

  • Question 9/10
    1 / -0

    The following question has four choices out of which ONLY ONE is correct.

    Energy of 24.6 eV is required to remove the first electron from a helium atom. The total energy (in eV) required to remove both the electrons from He atom would be

    Solutions

    He+ is a hydrogen-like ion since it has only one electron.
    The energy required for the removal of the second electron is given by

    ∴ Total energy required for the removal of both the electrons = 24.6 + 54.38 = 78.98 ≅ 79.0 eV

     

  • Question 10/10
    1 / -0

    Directions For Questions

    The successive ionisation energy values for an element 'X' are given below.

    (i) 1st ionisation energy = 410 kJ mol-1
    (ii) 2nd ionisation energy = 820 kJ mol-1
    (iii) 3rd ionisation energy = 1100 kJ mol-1
    (iv) 4th ionisation energy = 1500 kJ mol-1
    (v) 5th ionisation energy = 3200 kJ mol-1

    ...view full instructions


    Find out the number of valence electrons for an atom of 'X'.

    Solutions

    The ionisation energy values for valence electrons are comparable. Any quantum jump in the successive ionization energy values indicates that a stable configuration was acquired in the initial step. Among the given values, the biggest jump is between IE4 and IE5. Hence, there are four valence electrons for an atom of 'X' and removal of those electrons imparts the stable configuration of a noble gas to the element.

     

User Profile
-

Correct (-)

Wrong (-)

Skipped (-)


  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Click on Allow to receive notifications
×
Open Now