Transition Element Quiz-17

Transition Element Quiz-17

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry. .

Q1.  The highest magnetic moment is shown by the transition metal ion with the configuration

•   3d²
•   3d⁵
•   3d⁷
•   3d⁹

Solution
Magnetic moment =√(n(n+2) ) BM Where, n is the number of unpaired electrons. Maximum the value of unpaired electron, greater the value of magnetic moment. So, 3d⁵ has highest value of magnetic moment.

Q2.  The general electronic configuration of transition element is :

•   (n-1)d^1-5
•   (n-1)d^1-10 ns¹
•   (n-1)d^1-10 ns^0-2
•   None of these

Solution
Transition metals are d-block elements.

Q3.  The mineral from which copper is manufactured is:

•   Galena
•   Pyrite
•   Malachite
•   Chalcopyrite

Solution
Chalcopyrite is CuFeS₂

Q4.  Incorrect statement is

•   Atomic radii of Zr and Hf are same because of lanthanide contraction
•   Zn and Hg do not show variable valency
•   Across the lanthanides series, the basicity of lanthanide hydroxides decreases
•   Protactinium is transuranic element

Solution

Q5. Black Jack is an ore of

•   Cr
•   Sn
•   Zn
•   Ni

Solution
  Black Jack is an ore of zinc. Other ores of zinc are zincite (ZnO), calamine (ZnCO₃), zinc blende or black jack (ZnS).

Q6.  Pick out the correct statements from the following.
1.Cobalt (III) is more stable in octahedral complexes.
2.Zinc forms coloured ions or complexes.
3.Most of the d-block elements and their compounds are ferromagnetic.
4.Osmium shows (VIII) oxidation state.
5.Cobalt (II) is more stable in octahedral complexes.

•   1 and 2
•   1 and 3
•   2 and 4
•   1 and 4

Solution
CO³⁺ have higher charge density than CO²⁺, so CO³⁺ is more stable in octahedral complexes.
(ii) Zn exhibits only +2 oxidation state. So,
                                          Zn²⁺=[Ar]3d¹⁰,4s⁰
Since, it does not contain any unpaired electron, its compounds are colourless.
(iii) d-block elements are generally paramagnetic and sometimes diamagnetic, but not ferromagnetic.
(iv) Osmium and ruthenium are VIII group elements, so can exhibit the highest oxidation state +8 in their oxides, e.g., OsO₄.
Hence, statement 1 and 4 are correct.

Q7. A yellow ppt. is formed when H₂S is passed through an acidified solution of:

•   Co²⁺ions
•   Cd²⁺ions
•   Cu²⁺ions
•   Ni²⁺ions

Solution
CdS is yellow solid.

Q8. Iron, once dipped in concentrated H₂SO₄,does not displace copper from sulphate solution, because:

•   It is less reactive than copper
•   A layer of sulphate is deposited on it
•   A layer of oxide is deposited on it
•   None of the above

Solution
The formation of thin layer of oxide makes it passive.

Q9. In which of the following metallic bond is strongest?

•   V
•   Fe
•   Cr
•   Sc

Solution
Strength of metallic bond depends upon number of upon number of unpaired electron. As number of unpaired electron increases, the bond strength increases. So, Cr, Mo, W show stronger bonding due to maximum number of unpaired electrons

Q10.  Identify the alloy containing a non-metal as a constituent in it:

•   Bell metal
•   Bronze
•   Invar
• Steel

Solution
Carbon (non-metal) is present in steel.