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प्रश्न
Answer the following question:
Which element of the first transition series has lowest enthalpy of atomisation?
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उत्तर
Zinc is the element of the first transition series that has the lowest enthalpy of atomisation. The electronic configuration of zinc is: \[\ce{3d^10 4s^2}\]. This is because it has filled 3d-subshell and filled 4s-subshell so no unpaid electron is available for metallic bonding.
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संबंधित प्रश्न
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 has the highest m.p?
Account for the following:
Zn is not considered as a transition element.
Explain why Cu+ ion is not stable in aqueous solutions?
To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.
Which of the d-block elements may not be regarded as the transition elements?
How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.
Write balanced chemical equations for the conversion of `CrO_4^(2-)` to `Cr_2O_7^(2-)` in acidic medium and `Cr_2O_7^(2-)` to `CrO_4^(2-)`
in basic medium.
Electronic configuration of a transition element X in +3 oxidation state is [Ar]3d5. What is its atomic number?
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because ______.
The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain why?
Reactivity of transition elements decreases almost regularly from Sc to Cu. Explain.
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 |
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.
Mention any three processes where transition metals act as catalysts.
Sodium this sulphate is used in photography because of its:-
Account for the following:
Ce4+ is a strong oxidising agent.
Which one among the following metals of the 3d series has the lowest melting point?
The given graph shows the trends in melting points of transition metals:
Explain the reason why Cr has the highest melting point and manganese (Mn) has a lower melting point.
Describe the oxidising action of potassium dichromate and write the ionic equation for its reaction with iron (II) solution.
