English

Write the factors which are related to the colour of transition metal ions.

Advertisements
Advertisements

Questions

Write the factors which are related to the colour of transition metal ions.

Write the conditions of colour of transition metal ions.

Short Answer
Advertisements

Solution

  1. Metal ions exhibit the presence of incompletely filled d-orbitals.
  2. The presence of unpaired electrons in d-orbitals.
  3. The d-d transition of electrons due to absorption of radiation in the visible region.
  4. The metal ion in the complex undergoes a type of hybridisation.
  5. The geometry of the complex containing transition metal ions is described.
shaalaa.com
  Is there an error in this question or solution?
2023-2024 (July) Official

RELATED QUESTIONS

Explain why is Fe3+ more stable than Fe2+?


Which metal in the first transition series (3d series) exhibits + 1 oxidation state most frequently and why?


The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co

Answer the following: Which element shows only +3 oxidation state?


In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?


Which is a stronger reducing agent, Cr2+ or Fe2+ and why?


Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?


How would you account for the following:

The d1 configuration is very unstable in ions.


What are inner transition elements?


Complete and balance the following chemical equations

`MnO_4^(-) + H_2O + I^(-) ->`


Dissociation of H2S is suppressed in acidic medium.


Account for the following : 
 Ti4+ is colourless whereas V4+  is coloured in an aqueous solutions. 


Explain why Zn2+ salts are white whereas Cu2+ salts are coloured.


The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of Cr3+ ion is ______.


Although Zirconium belongs to 4d transition series and Hafnium to 5d transition series even then they show similar physical and chemical properties because ______.


Why EΘ values for Mn, Ni and Zn are more negative than expected?


A solution of \[\ce{KMnO4}\] on reduction yields either a colourless solution or a brown precipitate or a green solution depending on pH of the solution. What different stages of the reduction do these represent and how are they carried out?


Match the catalysts given in Column I with the processes given in Column II.

Column I (Catalyst) Column II (Process)
(i) \[\ce{Ni}\] in the presence of hydrogen (a) Zieglar Natta catalyst
(ii) \[\ce{Cu2C12}\] (b) Contact process
(iii) \[\ce{V2O5}\] (c) Vegetable oil to ghee
(iv) Finely divided iron (d) Sandmeyer reaction
(v) \[\ce{TiCl4 + Al (CH3)3}\] (e) Haber's Process
  (f) Decomposition of KCIO3

Match the solutions given in Column I and the colours given in Column II.

Column I
(Aqueous solution of salt)
Column II
(Colour)
(i) \[\ce{FeSO2.7H2O}\] (a) Green
(ii) \[\ce{NiCl2.4H2O}\] (b) Light pink
(iii) \[\ce{MnCl2.4H2O}\] (c) Blue
(iv) \[\ce{CoC12,6H2O}\] (d) Pale green
(v) \[\ce{Cu2 Cl2}\] (e) Pink
  (f) Colourless

Assertion: \[\ce{Cu^2+}\] iodide is not known.

Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.


When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, a yellow solution of compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C) can be crystallised from the solution. When compound (C) is treated with KCl, orange crystals of compound (D) crystallise out. Identify A to D and also explain the reactions.


It has been observed that first ionization energy of 5 d series of transition elements are higher than that of 3d and 4d series, explain why?


Read the passage given below and answer the following question.

Are there nuclear reactions going on in our bodies?

There are nuclear reactions constantly occurring in our bodies, but there are very few of them compared to the chemical reactions, and they do not affect our bodies much. All of the physical processes that take place to keep a human body running are chemical processes. Nuclear reactions can lead to chemical damage, which the body may notice and try to fix. The nuclear reaction occurring in our bodies is radioactive decay. This is the change of a less stable nucleus to a more stable nucleus. Every atom has either a stable nucleus or an unstable nucleus, depending on how big it is and on the ratio of protons to neutrons. The ratio of neutrons to protons in a stable nucleus is thus around 1 : 1 for small nuclei (Z < 20). Nuclei with too many neutrons, too few neutrons, or that are simply too big are unstable. They eventually transform to a stable form through radioactive decay. Wherever there are atoms with unstable nuclei (radioactive atoms), there are nuclear reactions occurring naturally. The interesting thing is that there are small amounts of radioactive atoms everywhere: in your chair, in the ground, in the food you eat, and yes, in your body.

The most common natural radioactive isotopes in humans are carbon-14 and potassium-40. Chemically, these isotopes behave exactly like stable carbon and potassium. For this reason, the body uses carbon-14 and potassium-40 just like it does normal carbon and potassium; building them into the different parts of the cells, without knowing that they are radioactive. In time, carbon-14 atoms decay to stable nitrogen atoms and potassium-40 atoms decay to stable calcium atoms. Chemicals in the body that relied on having a carbon-14 atom or potassium-40 atom in a certain spot will suddenly have a nitrogen or calcium atom. Such a change damages the chemical. Normally, such changes are so rare, that the body can repair the damage or filter away the damaged chemicals.

The natural occurrence of carbon-14 decay in the body is the core principle behind carbon dating. As long as a person is alive and still eating, every carbon-14 atom that decays into a nitrogen atom is replaced on average with a new carbon-14 atom. But once a person dies, he stops replacing the decaying carbon-14 atoms. Slowly the carbon-14 atoms decay to nitrogen without being replaced, so that there is less and less carbon-14 in a dead body. The rate at which carbon-14 decays is constant and follows first order kinetics. It has a half-life of nearly 6000 years, so by measuring the relative amount of carbon-14 in a bone, archeologists can calculate when the person died. All living organisms consume carbon, so carbon dating can be used to date any living organism, and any object made from a living organism. Bones, wood, leather, and even paper can be accurately dated, as long as they first existed within the last 60,000 years. This is all because of the fact that nuclear reactions naturally occur in living organisms.

Why is Carbon-14 radioactive while Carbon-12 not? (Atomic number of Carbon: 6)


Catalytic hydrogenation of benzene gives


Match List - I with List - II.

List - I List - II
(A) [Fe(CN)6]3− (i) 5.92 BM
(B) [Fe(H2O)6]3+ (ii) 0 BM
(C) [Fe(CN)6]4− (iii) 4.90 BM
(D) [Fe(H2O)6]2+ (iv) 1.73 BM

Choose the correct answer from the options given below.


The number of terminal oxygen atoms present in the product B obtained from the following reactions is:

\[\ce{FeCr2O4 + Na2CO3 + O2 -> A + Fe2O3 + CO2}\]

\[\ce{A + H^+ -> B + H2O + Na^+}\]


The disproportionation of \[\ce{MnO^{2-}_4}\] in acidic medium resulted in the formation of two manganese compounds A and B. If the oxidation state of Mn in B is smaller than that of A, then the spin-only magnetic moment (µ) value of B in BM is ______. (Nearest integer)


The oxidation state of Fe in [Fe(CO)5] is ______.


Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)


Give a reason for the following:

Zinc, cadmium and mercury are considered as d-block elements but not regarded as transition elements.


‘Spin only’ magnetic moment is the same for which of the following ions?

  1. Ti3+
  2. Cr2+
  3. Mn2+
  4. Fe2+
  5. Sc3+

Choose the most appropriate answer from the options given below:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×