0

Chemistry

Attempted 0/23 Correct 0 Score 0

Which of the following minerals contains calcium and aluminum?

  1. Orthoclase

  2. Themolite

  3. Albite

  4. Anorthite

  5. None of these


Correct Option: D
Explanation:

This option is correct because it belongs to felspar mineral and having Ca and Al to form a complex CaAl2Si2O8.

Which of the following are feldspar minerals? (A) Celsian (B) Crystobalite (C) Heulandite (D) Anorthite

  1. (A) and (D)

  2. (C) and (D)

  3. (A), (B) and (C)

  4. (C) and (B)

  5. None of these


Correct Option: A
Explanation:

This option is correct because the felspars are most important rock minerals in which Ba++, K+, Ca++, are linked with three dimensional framework of the SiO4 and AlO4 in tetrahedron. Celsian and anorthite are best known examples of  felspar. (Celsian = BaAl2Si2O8, and Anorthite = CaAl2Si2O8)

Which of the statements is false about the character of borazine?

  1. Borzine is isoelectronic structure of benzene.

  2. Both borazine and organic benzene are sp2 hybridised.

  3. Borazine is non-polar but benzene is polar.

  4. Partial delocalisation of pi electron occurs in borazine than benzene.

  5. None of these


Correct Option: C
Explanation:

This option is correct because in the case of borazine, B-N bond is polar due to electronegativity difference between B and N atoms while benzene is non-polar due to bonding between same atoms.

The colour of ____________ is not due to d-d transition.

  1. CrO42-

  2. [Ti(H2O)6]3+

  3. [CoCl4]2-

  4. [Cu(NH3)4]2+

  5. None of these


Correct Option: A
Explanation:

This option is correct because the colour is observed due LMCT spectra. In CrO42-, electrons transfer by oxygen to the vacant orbital of Cr6+ ion. A little transition spectra is observed.

Which of the following statements is true about SN1 reaction mechanism?

  1. Fast step is rate determining step.

  2. It is second order reaction.

  3. It is associative mechanism.

  4. It is unimolecular reaction.

  5. None of these


Correct Option: D
Explanation:

This option is correct because in SN1 mechanism, the single reacting complex ions substitute the ligand due to metal ligand breaking to form five coordinated intermediate complex.

Which of the following compounds shows MLCT transfer?

  1. HgO

  2. CdS

  3. Pb3(SbO4)2

  4. [Ru(2, 2bipyridyl)3]

  5. None of these


Correct Option: D
Explanation:

This option is correct because the compound [Ru (2, 2 bipyridyl) 3] shows MLCT due to the metal electron transfer to the pi antibonding molecular orbital of ligand. It is produced orange in colour.

Which of the following statements is correct about electron transfer outer sphere mechanism?

  1. The reductant and oxidant are labile.

  2. It is faster than inner sphere mechanism.

  3. Both species form bridge intermediate complex.

  4. The reducant and oxidant in transition state remain intact.

  5. None of these


Correct Option: D
Explanation:

This option is correct because the electrons transfer from reductant to oxidant in outer sphere mechanism, the reductant and oxidant in the transition state remain intact

(PNCl2)3 react with lead fluoride to form (A) P4N4Cl4F2 (B) P4N4Cl2F6 (C) (PNF2)3 (D) P3N3

  1. (A) and (B)

  2. (C) and (D)

  3. (A) and (D)

  4. (B) and (C)

  5. None of these


Correct Option: A
Explanation:

This option is correct because if the (PNCl2)3 reacts with lead fluoride, two tetramer derivatives P4N4Cl4Fand P4N4Cl2F6 are formed.

Which of the following complexes contains three isomeric forms?

  1. [Pt(NH3)(Py)(Cl)(Br)]

  2. [Pt(en)2(Cl)(Br)]

  3. [Pt(Cl)4]

  4. [Pt(NH3)2(Cl)(Br)]

  5. None of these


Correct Option: D
Explanation:

This option is incorrect because this complex shows two isomers.

Which of the following polymers are volan and quilon?

  1. Synthetic coordination polymer

  2. Step-growth polymer

  3. Chain growth polymer

  4. Natural coordination polymer

  5. None of these


Correct Option: A
Explanation:

This option is correct because the volan and quilon polymer are synthesised on reduction of CrO2Cl2 by methanol or ethanol in presence of carboxylic acid. This yield a solution of synthetic polymer. (R = methacrylate group is called volan, when R = stearate and myristate are called quilon polymer)

How many doublet state are possible in [Mn(H2O)6]++ complexes?

  1. 7

  2. 11

  3. 5

  4. 3

  5. None of these


Correct Option: A
Explanation:

This option is correct because the central metal atom of the complexes belong to the 3dconfiguration, which is correlated to ground state term of S6. These terms are split in to 11 excited states from which 4 is quartets excited and remaining 7 is doublet excited.

When the borazole is pyrolysed above 3400C, which of the following analogues compounds are formed?

  1. B6N6H10 and B5N5H8

  2. B3N3H3Br3 and B5N5H8

  3. B3N3H3Cl3 and B3N3H3Br3

  4. B3N3H3Cl3 and B6N6H10

  5. None of these


Correct Option: A
Explanation:

This option is correct because when borazole is pyrolysed above 3400C, it produces analogues compounds in the form of diphenyl and naphthalene like B6N6H10 and B5N5H8.

The zero magnetic moment of octahedral complexes K2NiF6 is due to

  1. low spin 3d6 Ni (IV) complex

  2. low spin 3d8 Ni(II) complex

  3. high spin 3d8 Ni(II) complex

  4. high spin 3d6 Ni (IV) complex

  5. none of these


Correct Option: A
Explanation:

This option is correct because the K2NiF6 shows the high spin character but actually cannot exhibit zero magnetic moment. Hence, these complexes behave as low spin in nature, the electrons are distributed in 6t2g and 0edue to distribution of electron. No unpaired electron occur, i.e. magnetic moment is zero in low spin.

Which of the following complexes X, Y and Z is/are inert or labile? (X) [V(NH3)6]+++ (Y) = [Co(CN)6]3- (Z) = [Cr(CN)6]3-

  1. X and Y are inert, Z is labile.

  2. X and Z are labile, Y is inert.

  3. X is inert, Y and Z are labile.

  4. X is labile, Y and Z are inert.

  5. None of these


Correct Option: D
Explanation:

This option is correct, because the complex  X is labile, they contain the unhybridised metal orbital through which the ligand is attached more quickly in this orbital. But Y and Z are inert due to lack of availability unhybridised metal orbital the ligand cannot be attached in this orbital. (Lability shows more fast reaction and inert shows slow  reaction).

Which of the following is the suitable reagent for the oxidation of Ce+3 into Ce+4?

  1. Bromate in neutral medium

  2. Zinc-amalgam

  3. Ammonium citrate-citric acid

  4. Tri-n-butyl phosphate

  5. None of these


Correct Option: A
Explanation:

This option is correct because the mixture of Ce are treated with oxidising agent bromate in neutral medium to form a pracipitate Ce(OH)4.

The compound, which exhibits Jahn-Teller distortion is __________.

  1. [Mn(H2O)6]2+

  2. [Mn(H2O)6]3+

  3. [Cr(H2O)6]3+

  4. [Fe(CN)6]4-

  5. None of these


Correct Option: B
Explanation:

This option is correct, because the [Mn(H2O)6]3+ compound is high spin compound. It is related to the 3d4 configuration and splits into 3t2g symmetrical and 1eunsymmetrical, which exhibit the strong Jahn – Teller distortion.

What is the increasing order of wavelengths of absorption for the complex ions? (A) [Cr(NH3)6]3+ (B) [CrCl6]3- (C) [Cr(H2O)6]3+ (D) [Cr(CN)6]3-

  1. D < B < A < C

  2. D < C < B < A

  3. D < A < C < B

  4. B < C < A < D

  5. None of these


Correct Option: D
Explanation:

It is the correct answer.

The electron transfer from [Fe(H2O)6]2+ to [Fe(H2O)6]3+ is likely to occur via.

  1. d-d transition

  2. inner sphere electron transfer

  3. SN1 mechanism

  4. Outer sphere electron transfer

  5. None of these


Correct Option: D
Explanation:

This option is correct because in redox reaction, an electron transfer occur through the intact coordination shell of the metal ion. This redox reaction may occur self exchange electron to homonuclear species.

Arrange the following metal complexes in order of their decreasing lability: (P) [AlF6]3- (Q) [SiF6]2-
(R) [PF6]1-
(S) [SF6]0

  1. P > Q > R > S

  2. P > R > Q > S

  3. S > R > Q > P

  4. S > Q > R > P

  5. None of these


Correct Option: A
Explanation:

This option is correct because the cationic charge of the complex increases but the lability of the complexe decreases.

Cis and trans complexes of the type [PtA2X2] are distinguished by __________.

  1. chromyl chloride test

  2. carbylamines test

  3. ring test

  4. the Kurnakov test

  5. none of these


Correct Option: D
Explanation:

This option is correct because the complexes cis and trans [PtA2X2] react with thiourea to give substituted product [Pt(tu)4]2+but Cl is replaced by NH3 to form [Pt(NH3)2(tu)2]2+. This is used in the thiourea reaction to the assigned structure, which is known as Kurnakov test. 

The treatment of [PtCl4]2- with two equivalent of NH3 ligand leads to the formation of [Pt(NH3)2Cl2]. The complex is

  1. Trans [PtCl2(NH3)2], due to stronger trans effect of Cl- compared to NH3.

  2. Trans [PtCl2(NH3)2], due to weaker trans effect of Cl- compared to NH3.

  3. Cis [PtCl2(NH3)2], due to weaker trans effect of Cl- compared NH3.

  4. Cis [PtCl2(NH3)2], due to stronger trans effect of Cl- compared to NH3.

  5. None of these


Correct Option: D
Explanation:

This option is correct  because the Cis [Pt(NH3)2Cl2] complex ions is formed when [Pt(Cl)4]2-react with NH3 to form [Pt(NH3)(Cl)3]- and again it reacts with NH3 to form Cis [Pt(Cl)2(NH3)2] complex, due to the stronger effect Cl- than NH3.

The orange colour of Cr2O72- is due to __________.

  1. the metal to ligand charge transfer transition

  2. ligand to metal charge transfer transition

  3. crystal field transition

  4. charge transfer complexes formation

  5. none of these


Correct Option: B
Explanation:

This option is correct because in the ions of Cr2O72-, the Cr have six oxidation state, due to fact that all the electrons are removed from Cr atom. Therefore, the oxygen atoms are low lying MOs of Cr atom in this condition Cr2O72-.

The number of absorption band observed in [Co(H2O)6]2+ and [CoF6]3- respectively are ________.

  1. 1 and 3

  2. 0 and 1

  3. 0 and 3

  4. 3 and 1

  5. None of these


Correct Option: D
Explanation:

This option is correct because [Co(H2O)6]2+ complexes ion in Co2+ are related to 3d7 electronic configuration and have F4 ground state term. It splits in to 4T1g(F),4T2g(F), 4A2g(F) and 4T1g(P), respectively, i.e. show 3 bands but other complexes ion spin allowed transition in 5T2and 5Eg one absorption band.

- Hide questions