Which theory explains the colour of transition metal complexes by considering the splitting of d-orbitals in a ligand field?

A. Valence Bond Theory

B. Molecular Orbital Theory

C. Crystal Field Theory

D. Ligand Field Theory

In an octahedral complex, which d-orbitals are raised in energy compared to a tetrahedral complex?

A. dxy, dxz, and dyz

B. dz^2 and dx^2-y^2

C. dx^2 and dy^2

D. All d-orbitals are raised equally

Which of the following is NOT a factor influencing the colour of complexes?

A. The oxidation state of the metal

B. The nature of the ligand

C. The coordination number of the complex

D. The atomic number of the metal

If a complex absorbs light in the blue region of the spectrum, which colour will it most likely appear to the human eye?

A. Blue

B. Green

C. Orange

D. Red

Which type of d-d transition is responsible for the colour in many transition metal complexes?

A. dxy -> dxz

B. dz^2 -> dx^2-y^2

C. dx^2 -> dy^2

D. dxz -> dyz

a) Explain the concept of d-orbital splitting in the context of Crystal Field Theory. How does it relate to the formation of coloured complexes in transition metals? [4]

b) Differentiate between tetrahedral and octahedral complexes in terms of d-orbital splitting. [3]

a) Describe how the observed colour of a complex ion is related to the light it absorbs. [3]

b) Using the complementary colour theory, predict the observed colour of a complex that absorbs green light. [2]

a) How do d-electrons influence the reactivity of transition metal complexes? [3]

b) Explain the factors that can influence the colour of complexes formed by transition metals. [4]

a) Describe the role of d-orbitals in the formation of complex ions in transition metals. [3]

b) Why do some transition metal complexes appear coloured while others are colourless? [3]

c) Explain how the variation in oxidation states of transition metals contributes to their ability to form coloured complexes. [3]

a) What is the significance of Crystal Field Theory in explaining the properties of transition metal complexes? [3]

b) How does the geometry of a complex (tetrahedral vs. octahedral) influence its colour? [4]

c) Describe the industrial applications that exploit the coloured nature of transition metal complexes. [3]

Which of the following ligands would most likely cause the largest splitting of d-orbitals in an octahedral complex?

A. Water

B. Chloride ion

C. Cyanide ion

D. Hydroxide ion

In the context of coloured complexes, what is the significance of the term 'spectrochemical series'?

A. It refers to the series of colours observed in a spectrum.

B. It is a list of ligands arranged in order of their ability to split d-orbitals.

C. It is a series of complex ions arranged in order of their stability.

D. It refers to the series of wavelengths absorbed by a complex.

Which of the following statements about tetrahedral complexes is true?

A. They have larger d-orbital splitting than octahedral complexes.

B. They do not exhibit colour.

C. They have smaller d-orbital splitting than octahedral complexes.

D. All tetrahedral complexes are colourless.

Why do some transition metal complexes appear colourless?

A. They do not have d-d transitions.

B. They absorb light in the ultraviolet region.

C. They reflect all colours of visible light.

D. They have complete d-orbitals.

Which of the following is an application of coloured complexes in chemical analysis?

A. Determination of metal ion concentration

B. Measurement of pH

C. Identification of organic compounds

D. Determination of molecular weight

a) Explain the concept of complementary colour theory and its relevance in predicting the observed colours of transition metal complexes. [3]

b) A complex ion absorbs light with a wavelength of 480 nm. Using the complementary colour theory, predict its observed colour. [2]

c) How is the colour wheel used in predicting observed colours of complexes? [3]

a) Why is Zinc (Zn) not considered a typical transition element, despite being in the d-block? [3]

b) Compare the electron configuration of Zinc with other first-row d-block elements. [3]

c) How does the unique electron configuration of Zinc influence its chemical properties compared to other transition metals? [4]

a) Describe the process of d-orbital splitting in an octahedral complex. [3]

b) How does the splitting differ in a tetrahedral complex? [3]

c) Given that a certain octahedral complex appears green, which part of the visible spectrum is it likely absorbing? [2]

d) Explain the role of ligands in influencing the colour of a complex. [4]

a) What is the significance of electron transitions between split d-orbitals in determining the colour of a complex? [3]

b) Describe the relationship between the absorbed light and the observed colour of a complex. [3]

c) How does the number of d-electrons influence the reactivity and colour of transition metal complexes? [3]

d) Explain the concept of complementary colours and its application in predicting the colour of complexes. [3]

a) How does Crystal Field Theory explain the formation of coloured complexes in transition metals? [4]

b) A certain complex ion absorbs light with a wavelength of 520 nm. Using the complementary colour theory, predict its observed colour. [2]

c) Describe the role of d-electrons in determining the properties of transition metal complexes. [3]

d) How are coloured complexes used in chemical analysis? Provide an example. [3]