Home
Class 12
CHEMISTRY
(A) Atomic size of silver is almost equa...

(A) Atomic size of silver is almost equal to that of gold.
(R) d subshell has low penetration power and produce poor shielding effect.

A

Both (A) and (R) are true and (R) is the correct explanation of (A)

B

Both (A) and (R) are true and (R) is not the correct explanation of (A)

C

(A) is true but (R) is false

D

Both (A) and (R) are false

Text Solution

Verified by Experts

The correct Answer is:
B
Both (A) and (R) are true and (R) is not the correct explanation of (A)
Promotional Banner

Topper's Solved these Questions

  • D-BLOCK ELEMENTS

    AAKASH SERIES|Exercise OBJECTIVE EXERCISE-3 (PREVIOUS NEET/AIPMT QUESTIONS)|43 Videos

  • D - BLOCK ELEMENTS

    AAKASH SERIES|Exercise PRACTICE EXERCISE|50 Videos

  • DILUTE SOLUTIONS

    AAKASH SERIES|Exercise EXERCISE - 1.2|55 Videos

Similar Questions

Explore conceptually related problems

(A): The atomic size of gallium is less than expected (R): In gallium the 3^(10) delectrons do not shield effectively

Assertion (A) While going from left to right of the periodic table, the atomic size decreases more rapidly for the 3d-series compared to the 4 f-series of elements. Reason R 3d-electrons experience lesser shielding then 4 f-electrons. The correct answer is

Regarding lanthanide contraction, some statements are given a) It arises because of the poor shielding effect of 5f-electrons b) The atomic radii and ionic radii steadily decrease from Ce to Lu c) The crystal structures and other properties are similar d) The seperation of lanthanides from one another is difficult from their salt solutions. The correct statements are

The amount of energy released when an electron is added to an isolated gaseous atom to produce a monovalent anion is called electron affinity or first electron affinity or electron gain enthalpy. The first electron is given a negative sign as the addition of an electron to a neutral atom is an exoergic process. The addition of electron to A^(-1) requires energy to overcome the force of repulsion. Thus, the second electron affinity is an endoergic process. The magnitude of electron affinity depends on a number of factors such as (i) atomic size (ii) effective nuclear charge (iii) screening effect (iv) half and fully filled orbitals and (v) shape of orbital. In general, electron affinity increases as the atomic radii decrease in a period. However, there are exceptions when the atoms have stable configurations. In a group, electron affinity decreases as the size increases. However, the members of 3rd period have somewhat higher values than the members in the 2nd period of the same subgroups. Which of the following species has the highest electron affinity?

An orbital is designated by certain values of first three quantum numbers (n, l and m) and according to Pauli.s exclusion principle, no two electrons in a atom can have all the for quantum numbers equal. N, l and m denote size, shape and orientation of the orbital. The permissible values of n are 1,2,3.... prop while that of 1 are all possible integral values from 0 to n-n. Orbitals with same values of n and 1 but different values of m (where m can have any integral values from 1 to +1 including zero) are of equal energy and are called degenerate orbitals. However degeneracy is destroyed in homogeneous external magnetic field due to different extent of interaction between the applied field and internal electronic magnet of different orbitals differing in orientations. In octahedral magnetic field external magnetic field as oriented along axes while in tetrahedral field the applied field actas more in between the axes than that on the axes themselves. For 1=0, 1,2,3,...., the states (called sub-shells) are denoted by the symbol s,p,d,f.....respectively. After f, the subshells are denoted by letters alphabetically 1 determines orbital angular motion (L) of electron as L = sqrt(l(l+1))(h)/(2pi) ON the other hand, m determines Z-component of orbital angular momentum as L_(Z) = m((h)/(2pi)) Hund.s rule states that in degenerate orbitals electrons do not pair up unless and until each each orbitals has got an electron with parallesl spins Besides orbital motion,an electron also posses spin-motion. Spin may be clockwise and anticloskwise. Both these spin motions are called two spins states of electrons characterized by spin Q.N (s) : s = +(1)/(2) and = -(1)/(2) respectively The sum of spin Q.N. of all the electrons is called total spin(s) and 2s+1 is called spin multiplicity of the configuration as a whole. The spin angular momentum of an electron is written as L_(s) = sqrt(s(s+1))(h)/(2pi) According to Hund.s rule, the distribution of electron within the various orbitals of a given sub-shell is one which is associated with

An orbital is designated by certain values of first three quantum numbers (n, l and m) and according to Pauli.s exclusion principle, no two electrons in a atom can have all the for quantum numbers equal. N, l and m denote size, shape and orientation of the orbital. The permissible values of n are 1,2,3.... prop while that of 1 are all possible integral values from 0 to n-n. Orbitals with same values of n and 1 but different values of m (where m can have any integral values from 1 to +1 including zero) are of equal energy and are called degenerate orbitals. However degeneracy is destroyed in homogeneous external magnetic field due to different extent of interaction between the applied field and internal electronic magnet of different orbitals differing in orientations. In octahedral magnetic field external magnetic field as oriented along axes while in tetrahedral field the applied field actas more in between the axes than that on the axes themselves. For 1=0, 1,2,3,...., the states (called sub-shells) are denoted by the symbol s,p,d,f.....respectively. After f, the subshells are denoted by letters alphabetically 1 determines orbital angular motion (L) of electron as L = sqrt(l(l+1))(h)/(2pi) ON the other hand, m determines Z-component of orbital angular momentum as L_(Z) = m((h)/(2pi)) Hund.s rule states that in degenerate orbitals electrons do not pair up unless and until each each orbitals has got an electron with parallesl spins Besides orbital motion,an electron also posses spin-motion. Spin may be clockwise and anticloskwise. Both these spin motions are called two spins states of electrons characterized by spin Q.N (s) : s = +(1)/(2) and = -(1)/(2) respectively The sum of spin Q.N. of all the electrons is called total spin(s) and 2s+1 is called spin multiplicity of the configuration as a whole. The spin angular momentum of an electron is written as L_(s) = sqrt(s(s+1))(h)/(2pi) The orbital angular momentum of electron (l=1) makes an angles of 45^(@) from Z-axis. The L_(z) of electron will be

AAKASH SERIES-D-BLOCK ELEMENTS-OBJECTIVE EXERCISE-4 (ASSERTION (A) & REASON (R) TYPE QUESTIONS )
  1. (A) The purple colour of KMnO4 is due to the charge transfer transitio...

    Text Solution

    |

  2. (A) The highest oxidation state of Os is +8. (R) Osmium is a 5d elem...

    Text Solution

    |

  3. (A) Atomic size of silver is almost equal to that of gold. (R) d sub...

    Text Solution

    |

  4. (A) Cr^(+2) is strong reducing agent in aqueous solution. (R) Cr^(+2...

    Text Solution

    |

  5. (A) Potassium dichromate is used as a primary standard in volumetric a...

    Text Solution

    |

  6. (A) Potassium ferrocyanide and potassium ferricyanide both are paramag...

    Text Solution

    |

  7. (A) Zn^(+2) is diamagnetic (R) The electrons are lost from 4s orbita...

    Text Solution

    |

  8. (A) d block elements are transitioned between s-block metals and p-blo...

    Text Solution

    |

  9. (A) E.C of Pd is [Kr] 4d^(8)5s^(2) (R) Palladium contains 8e^(-) in ...

    Text Solution

    |

  10. (A) Sc exhibit variable oxidation states. (R) Sc is not a transition...

    Text Solution

    |

  11. (A) : Cu^(+2)(aq) is more stable than Cu^(+)(aq) (R): Heat of hydrat...

    Text Solution

    |

  12. (A) Cr^(+2) is reducing in nature. (R) Half filled t(zg) level in Cr...

    Text Solution

    |

  13. (A) Many copper(I) compounds are unstable in aqueous solution. (R) ...

    Text Solution

    |

  14. (A) The number of unpaired electrons in the following gaseous ion Mn^...

    Text Solution

    |

  15. (A) MnO(4)^(-1) is strong oxidizing agent. (R) Mn^(+2) is stable wit...

    Text Solution

    |

  16. (A) The free gaseous Cr atom has six unpaired electrons. (R) Half fi...

    Text Solution

    |

  17. (A) E^(@) for Mn^(+3)//Mn^(+2) is more positive than Cr^(3+)//Cr^(+2) ...

    Text Solution

    |

  18. (A) K2Cr2O7 is used as primary standard in volumetric analysis. (R) ...

    Text Solution

    |

  19. (A) Solution of Na2CrO4 in water is intensely coloured. (R) Oxidatio...

    Text Solution

    |

  20. (A) Elements of 4f sries are called Lanthanides (R) Lanthanum Belong...

    Text Solution

    |