Home
Class 12
CHEMISTRY
Which of the following are correct about...

Which of the following are correct about Zn,Cd,Hg
I) They exhibit enthalpy of atomisation as the d-subshell is full
II) Zn,Cd do not show variable oxidation states, Hg can show +1,+2 states
III) Compounds of `Zn,Cd,Hg` are paramagnetic
IV) They are soft metals

A

I, II, III

B

I, III

C

II, IV

D

IV only

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements about Zn, Cd, and Hg are correct, let's analyze each statement step by step. ### Step 1: Analyze the Electronic Configuration - **Zinc (Zn)**: [Ar] 3d^10 4s^2 - **Cadmium (Cd)**: [Kr] 4d^10 5s^2 - **Mercury (Hg)**: [Xe] 4f^14 5d^10 6s^2 All three elements have completely filled d-subshells (3d^10, 4d^10, and 5d^10). ### Step 2: Evaluate Statement I **Statement I**: They exhibit enthalpy of atomization as the d-subshell is full. - Since the d-subshell is completely filled, there are no unpaired electrons, leading to weaker metallic bonding. Therefore, the enthalpy of atomization is lower, not higher. - **Conclusion**: This statement is **incorrect**. ### Step 3: Evaluate Statement II **Statement II**: Zn and Cd do not show variable oxidation states, Hg can show +1, +2 states. - Zinc and cadmium typically exhibit a +2 oxidation state, while mercury can exhibit both +1 and +2 oxidation states. - **Conclusion**: This statement is **correct**. ### Step 4: Evaluate Statement III **Statement III**: Compounds of Zn, Cd, and Hg are paramagnetic. - Since all three elements have completely filled d-subshells, they do not have unpaired electrons, which means they are diamagnetic, not paramagnetic. - **Conclusion**: This statement is **incorrect**. ### Step 5: Evaluate Statement IV **Statement IV**: They are soft metals. - The presence of completely filled d-subshells results in weaker metallic bonds, making them soft metals. - **Conclusion**: This statement is **correct**. ### Final Conclusion The correct statements about Zn, Cd, and Hg are: - Statement II: Correct - Statement IV: Correct Thus, the correct answer is that statements II and IV are correct. ### Summary of Correct Statements - **Correct Statements**: II and IV - **Incorrect Statements**: I and III
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • d-BLOCK ELEMENTS

    VK JAISWAL ENGLISH|Exercise ASSERTION-REASON TYPE QUESTIONS|32 Videos

  • d-BLOCK ELEMENTS

    VK JAISWAL ENGLISH|Exercise SUBJECTIVE PROBLEMS|6 Videos

  • CO-ORDINATION COMPOUNDS

    VK JAISWAL ENGLISH|Exercise LEVEL 2|144 Videos

  • ENVIRONMENTAL CHEMISTRY

    VK JAISWAL ENGLISH|Exercise ASSERTION-REASON TYPE QUESTIONS|14 Videos

Similar Questions

Explore conceptually related problems

How many of the following show variable oxidation states in their compounds? Sc,Cr,Cu,Zn,Fe,Hg,La

Zn and Hg do not show variable valency like d- block elements because-

Knowledge Check

  • Most of the transition metals exhibit (i) paramagnetic behaviour (ii) diamagnetic behaciour (iii) variable oxidation states (iv) formation of coloured ions

    A
    (ii), (iii) and (iv)
    B
    (i) , (iii) and (iv)
    C
    (i), (ii) and (iii)
    D
    (i), (ii) and (iv)

    • Similar Questions

    Explore conceptually related problems

    Consider following properties of the noble gases. I. They readily form compounds which are colourless. II: They generally do not form ionic compounds. III: Xenon has variable oxidation states in its compounds IV : the smaller He and Ne do not form clathrate compounds. Select correct properties.

    Most of the transition metals exhibit (i) paramagnetic behaviour (ii) diamagnetic behaciour (iii) variable oxidation states (iv) formation of coloured ions

    Give reason for the following : (i) Mn shows the highest oxidation state of +7 with oxygen but with fluorine, it shows the highest oxidation state of +4 (ii) Transition metals show variable oxidation states. (iii) Actinoids show irregularities in their electronic configurations.

    Account for the following : (i) Oxygen does not show an oxidation state of + 4 and + 6 like sulfur . (ii) NO_2 readily forms a dimer. (iii) Fluorine always exhibits and oxidation state of -1 only in its compunds

    Which statement among the following are correct ? I. Ce^(+3) is an oxidizing agent & colourless. II. Lu^(3+) is colourless. III. Actinoids exhibit a higher number of oxidation states than lanthanoid IV. All 3d elements give H_(2) with 1 M HCl

    Which of the following can show geometrical isomerism? (i) Propene (ii) But-1-ene (iii) But-2-ene (iv) Pent-2-ene

    The transition element ( with few exceptions ) show a large number of oxidation states . The various oxidation states are related to the electronic configuration of their atoms. The variable oxidation states of a transition metal is due to the involvement of (n-1)d and outer ns electrons . For the first five elements of 3d transition series , the minimum oxidation state is equal to the number of electrons in 4s shell and the maximum oxidation state is equal to the sum of 4s and 3d electrons. The relative stability of various oxidation states of a given element can be explained on the basis of stability of d^(0),d^(5) and d^(10) configuration . In which of the following pairs , the first species is more stable than second one

    Home
    Profile