1.The correct increasing order of splitting power of ligands according to spectrochemical series is
(a) Cl– < OH– < CN–
(b) Cl– < CN– < OH–
(c) OH– < Cl– < CN–
(d) none of these
Answer: (a)
Video Explanation
2.Tetraamminecopper(II) sulphate is _ in colour.
(a) violet
(b) blue
(c) green
(d) red
Answer: (b)
Explanation
The brilliant dark blue-violet color of tetraamminecopper(II) sulfate solution is due to presence of [Cu(NH3)4]2+. Often, the dark blue-violet color is used as a positive test to verify the presence of Cu2+ in a solution.
This compound can be prepared by adding concentrated solution of ammonia to a saturated aqueous solution of copper sulfate pentahydrate followed by precipitation of the product with ethanol or isopropanol.
4 NH3 + CuSO4·5H2O →[Cu(NH3)4]SO4·H2O+ 4 H2O
Video Explanation
3.Transition elements exhibit variable valency because they release electrons from
(a) ns orbitals
(b) (n-1)d orbitals
(c) (n-1)d & ns orbitals
(d) none of these
Answer: (c)
Explanation
The ability of the transition metals to exhibit variable valency is generally attributed to the availability of more electrons in the (n−1)d orbitals which are closer to the outermost ns orbital in energy levels.
in excited state, the ns and (n-1)d electrons become bonding and thus give variable oxidation states to the atoms of transition elements.
Thus, transition elements show variable valencies due to involvement of penultimate d shell electrons.
Video Explanation
4.The compound, which does not contain a metal-carbon bond is
(a) Al(OC2H5)3
(b) C2H5MgBr
(c) Ni(CO)4
(d) none of these
Answer: (a)
Video Explanation
5.The coordination number of the transition element in [Pt Cl NO2 (NH3)4]2- is
(a) 2
(b) 6
(c) 4
(d) 8
Answer: (b)
Explanation
Platinum is bonded with three types of ligands,
Ammonia which is monodentate ligand is of four in number.
Chloride which is also a monodentate ligand is one in number.
Nitro ligand also one in number.
Therefore,
Co-ordination number of Platinum =1+1 +4
=2+4= 6
hence the coordination no. of Pt is 6
Video Explanation
6.For K2 (Cu(CN)4) which one is correct
(a) Potassium tetra cyano recuperate
(b) Co-ordination number is 2
(c) The ligand is positively charged
(d) none of these
Answer: (d)
Explanation
a) the name of k2 cu(cn)4 is potassium tetracyanocuprate (II)
b) Coordination no is 4.
The important detail here is that the potassium cation (K) outside of the square brackets is not part of the coordination complex. It is simply ionically bonded to the complex that exists as a complex anion. The actual coordination complex is:
[Cu(CN)4]2−
c) Each cyanide ion ligand has a -1 charge.
Video Explanation
- The melting points and boiling points up to the middle of 3d- series
(a) Increases
(b) Decreases
(c) Remain same
(d) No regular trend
Answer: (a)
Explanation
The d-block elements with more number of unpaired e− will have high melting point as more number of unpaired e −
present, stronger will be the metallic bond formation. Hence requirement of heat to loosen the bond will be high.
the melting point of 3d-series gradually increases from Sc to V and it reach a maximum value for Cr and after it the melting point slowly decreases. Because of with increase in atomic mass and atomic number, the number of unpaired electrons of transition metals increases.
Video Explanation
- When light is exposed to transition element then electrons jump from lower orbitals to higher orbitals in that show color
(a) Orbitals of f-subshell
(b) Orbitals of d-subshell
(c) none of these
(d) Both A & B
Answer: (b)
Video Explanation
- Non-stoichiometric compounds of transition elements are called
(a) Hydrates
(b) Hydrides
(c) Interstitial compounds
(d) None of these
Answer: (c)
Explanation
hydrate-In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understood.
hydride-In chemistry, a hydride is the anion of hydrogen, H⁻, or more commonly it is a compound in which one or more hydrogen centres have nucleophilic, reducing, or basic properties. In compounds that are regarded as hydrides, the hydrogen atom is bonded to a more electropositive element or groups.
Video Explanation
- Which of the following can form a chelate
(a) Ammine
(b) Oxalate
(c) Carbonyl
(d) Cyano
Answer: (b)
Explanation
In chelation, ring formation occurs because two atoms from the same ligand coordinate with the metal atom. This cannot happen if the ligand is monodentate.
Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These ligands are called chelants, chelators, chelating agents, or sequestering agents.
Oxalate is a bidentate ligand hence it forms a chelate. It can coordinate with both of its negatively charged O atoms.
carbonyl, cyanide and ammonia are monodentate ligands. They do not form chelates.
Video Explanation
- Which of the following d orbitals take part in the octahedral complex with d2sp3 hybridisation?
(a) dxy, dyz
(b) dxz, dx2−y2
(c) dx2−y2, dz2
(d) dz2, dxz
Answer: (c)
Video Explanation
- When the central atom of coordination compound is sp3d2 hybridization the expected geometry will be
(a) Tetrahedral
(b) Square planar
(c) Trigonal bipyramidal
(d) Octahedral
Answer: (d)
Video Explanation
- In the production of wrought iron Mg Si and P are removed in the form of
(a) Oxides
(b) Silicates
(c) Slag
(d) none of these
Answer: (c)
Explanation
The iron obtained from Blast furnace contains about 4% carbon and many impurities in smaller amount (e.g., S,P,Si,Mn). This is known as pig iron and cast into a variety of shapes.
Video Explanation
- Which of the following is a bidentate ligand?
(a) CH3NH2
(b) C2O42-
(c) CH3CN
(d) all of these
Answer: (b)
Video Explanation
- Which of the following is typical transition metal?
(a) Sc
(b) Y
(c) Cd
(d) Co
Answer:(d)
Explanation
Typical transition elements:
The transition elements usually have partially filled d-orbitals such as Fe , Co ,Ni , etc. are called typical transition elements.
Non-typical transition elements:
The elements present in the d-block that have completely filled d-orbitals are called non-typical transition elements.
The non-typical transition elements are Zn,Cd and Hg.
Video Explanation
- What is the formula of hematite?
(a) Fe3O4
(b) FeSO4.7H2O
(c) Fe2O3
(d) FeCl3
Answer: (c)
Explanation
Ferric oxide(Fe2O3) occurs in nature as haematite. It is a red powder, insoluble in H2O and not acted upon by air or H2O. It is amphoteric in nature and reacts with acids and alkalis and used as a catalyst in the oxidation of CO to CO2 in the Bosch process.
Video Explanation
- Which compound forms double salt with sulphates of alkali metals?
(a) Ferric oxide
(b) Silver nitrate
(c) Ferric chloride
(d) Ferrous sulphate
Answer: (d)
Explanation
Ferrous sulphate forms double salts with sulphates of alkali metals with general formula R2SO4.FeSO4.6H2O. With ammonium sulphate, it forms a double salt known as Mohr’s salt. It ionises in solution to gives Fe2+, NH4+ and SO42- ions.
Video Explanation
- Which of the following is why the atomic radii of the second and third transition series are almost same?
(a) Actinoid contraction
(b) Filled d-orbital
(c) Lanthanoid contraction
(d) none of these
Answer: (c)
Explanation
In the atoms of the second transition series, the number of shells increases and so, their atomic radii is greater than that of the first transition series. The atomic radii of the second and third transition series are almost same due to lanthanoid contraction.
Video Explanation
- Which of the following is not a very hard metal?
(a) Chromium
(b) Molybdenum
(c) Tungsten
(d) Zinc
Answer: (d)
Explanation
Greater the number of unpaired electrons, stronger is the bonding due to overlapping of unpaired electrons between different metal atoms. Cr, Mo and W have maximum unpaired d-electrons and are harder metals whereas Zn, Cd and Hg are not very hard due to the absence of unpaired electrons.
Video Explanation
- Some salts containing two different metallic elements give test for only one of them in solution, such salts are
(a) double salts
(b) normal salts
(c) complex salts
(d) None of these
Answer: (c)
Video Explanation
- IUPAC name of [Pt(NH3)2Cl(NO2)] is
(a) Platinum diamminechloronitrite
(b) Chloronitrito-N-ammineplatinum (II)
(c) Diamminechloridonitrito-N-platinum (II)
(d) Diamminechloronitrito-N-plantinate (II)
Answer: (c)
Video Explanation
- The sum of coordination number and oxidation number of the metal M in the complex [M(en)2(C2O4)]Cl (where (en) is ethylenediamine) is
(a) 9
(b) 6
(c) 7
(d) 8
Answer: (a)
Video Explanation
- The type of isomerism shown by the complex [CoCl2(en)2] is
(a) Geometrical isomerism
(b) Coordination isomerism
(c) Linkage isomerism
(d) Ionization isomerism
Answer: (a)
Video Explanation
- Which of the following is paramagnetic?
(a) [CoBr]42-
(b) Mo(Co)6
(c) [Pt(en)Cl2]
(d) [Co(NH3)6]3+
Answer: (a)
Explanation
Co2+ = (3d5)
Bromine is a weak ligand but it is known that all tetrahedral complexes are high-spin regardless of the splitting power of the ligand. The low spin arrangement has five unpaired electrons in the d-orbital. So it is paramagnetic in nature.
all other are strong ligands so they paired up electrons. so they not show paramagnetism.
Video Explanation
- How many unpaired electrons are present in [CoF6]3- complex?
(a) 4
(b) zero
(c) 2
(d) 3
Answer: (a)
26/31.Which one can form complex ?
(a) Na
(b) Cr
(c) Li
(d) K
Answer: (b)
Video Explanation
27/32.Which one of the following is not an alkali metal ??
(a) Francium
(b) Caesium
(c) Rubidium
(d) Radium
Answer: (d)
Video Explanation
28/33.Li is different from its family members due to________?
(a) Small size
(B) High charge density
(c) Less electropositivity
(d) All of the above
Answer: (d)
Video Explanation
29/34.Which one is least ionic in nature and decompose on heating ?
(a) LiOH
(b) NaOH
(c) NaOH
(d) CsOH
Answer: (a)
Video Explanation
30/35.Which ion will have maximum value of heat of hydration ?
(a) A1+3
(b) Cs+
(c) Ba+
(d) Mg+2
Answer: (b)
Video Explanation
