NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.: Chemistry MCQs (Practice_Test 21 of 31)
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- Given that nickel metal can be written as [Ar] 4s2 3d8, which is the correct representation for the Ni2 + ion.
- [Ar] 4s0 3d8
- [Ar] 4s2 3d6
- [Ar] 4s1 3d7
- [Ar] 4s0 3d5
- correct response not given
- Use the following information to answer questions 27,28 and 29 related to the crystal-field theory of coordination compounds. Ferric ion (Fe3 +) forms the complexes FeF63-and Fe (CN) 63-with fluoride (F-) and cyanide (CN-) ions. Also, F-is a weaker-field ion than is CN-in the spectrochemical series, i.e. … F-< ________ < CN-. We would expect FeF63-to:
- have a larger crystal field splitting energy than Fe (CN) 63-.
- have a smaller magnetic moment than Fe (CN) 63-.
- absorb light at a longer wavelength (lower energy) than Fe (CN) 63-.
- be more soluble than Fe (CN) 63-.
- Use the following information to answer questions 27,28 and 29 related to the crystal-field theory of coordination compounds. Ferric ion (Fe3 +) forms the complexes FeF63-and Fe (CN) 63-with fluoride (F-) and cyanide (CN-) ions. Also, F-is a weaker-field ion than is CN-in the spectrochemical series, i.e. … F-< ________ < CN-. We would expect Fe (CN) 63-to:
- have a smaller crystal-field splitting energy than FeF63-.
- have a smaller magnetic moment than FeF63-.
- absorb light at a longer wavelength (lower energy) than FeF63-.
- be more soluble than FeF63-.
- Use the following information to answer questions 27,28 and 29 related to the crystal-field theory of coordination compounds. Ferric ion (Fe3 +) forms the complexes FeF63-and Fe (CN) 63-with fluoride (F-) and cyanide (CN-) ions. Also, F-is a weaker-field ion than is CN-in the spectrochemical series, i.e. … F-< ________ < CN-. We would expect both FeF63-and Fe (CN) 63-to form:
- linear structures.
- tetrahedral structures.
- square planar structures.
- octahedral structures.
- ________
- What is the oxidation state of chromium, AND the coordination number, for the coordination compound, [Cr (en) 2 (OH) 2] Cl?
- + 2,4
- + 3,4
- + 3,5
- + 3,6
- + 5,6
- All coordination compounds which contain a Zn2 + transition metal ion are colorless. Which of the following statements best explains this observation?
- Zn2 + contains unpaired electrons so it should be colorless.
- All of the 3d orbitals in Zn2 + are filled; therefore, the transfer of an electron cannot occur.
- Compounds containing Zn2 + absorb only blue light so they appear colorless.
- Compounds containing Zn2 + absorb only red light so they appear colorless.
- There is insufficient information to explain this observation.
- Coordination compounds which contain cyanide, CN-, ligands tend to be yellow whereas coordination compounds which contain water, H2O, ligands tend to be blue or green because:
- the complexes diffract light at different angles.
- cyanide is a weak-field ligand and water is a strong-field ligand.
- cyanide is a strong-field ligand and water is a weak-field ligand.
- cyanide compounds absorb yellow light and water compounds absorb blue or green light.
- The basic premise of the question is incorrect because both water and cyanide are colorless and accordingly cannot influence the color of the coordination compounds.
- In the Qualitative Analysis scheme, the confirmatory test for the Co2 + ion was the formation of the blue Co (SCN) 42-complex ion. Assume that the SCN-ligand is a strong-field ligand and that this species is tetrahedral, and determine the number of unpaired electrons in this complex ion.
- 1
- 2
- 3
- 4
- 5
- In the crystal field model for an octahedral complex, the dz2 and dx2 − y2 orbitals (eg set) are at higher energy than the dxy, dxz and dyz orbitals (t2g set) . Which one of the following statements best explains this behavior?
- The eg orbitals experience less electrostatic repulsion with the negative point charges than the t2g orbitals.
- The eg orbitals experience more electrostatic repulsion with the negative point charges than the t2g orbitals.
- The t2g orbitals point directly at the negative point charges.
- The splitting of the two sets of orbitals is also present in the free ion and therefore the negative point charges have no effect.
- The eg orbitals are at higher energy because there are only two of them.
- What is the oxidation state of the metal ion in the complex Ni (NH3) 6Cl2?
- -1
- 0
- + 1
- + 2
- + 3
- How many total isomers (structural isomers and stereoisomers) exist for the complex ion [Co (NH3) 5Cl] 2 + ?
- 1
- 2
- 3
- 4
- 6
- Which of the following compounds would be paramagnetic?
- Sc (NH3) 63 + (high spin)
- Zn (OH) 42- (tetrahedral)
- Co (NH3) 63 + (high spin)
- Fe (CN) 64- (low spin)
- Why are many coordination compounds colored?
- The equilibrium established between the coordination compounds and air lies on the product side.
- The energy required to excite an electron to an excited state is often the same as the energy of light in the visible region.
- The Crayola Corporation likes it that way.
- They all absorb water vapor, which normally hides all of the colors