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प्रश्न
Why do the transition elements have higher enthalpies of atomisation?
Explain giving reason:
The enthalpies of atomisation of the transition metals are high.
How would you account for the following?
The transition elements exhibit high enthalpies of atomization.
How would you account for the following:
The transition elements have high enthalpies of atomization?
Give reasons for the following:
Transition elements have high enthalpies of atomization.
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उत्तर
- Transition elements have high enthalpies of atomization due to the presence of many unpaired electrons in their atoms.
- Unpaired electrons lead to strong interatomic interactions and stronger metallic bonding between atoms.
- The stronger the metallic bonds, the more energy is required to break these bonds, resulting in higher enthalpies of atomization.
- Elements of the second and third transition series have even higher enthalpies due to more frequent metal-metal bonding.
- This strong bonding explains their high melting and boiling points as well.
संबंधित प्रश्न
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
Answer the following: Which element is a strong oxidising agent in +3 oxidation state and why?
Which of the 3d series of the transition metals exhibits the largest number of oxidation states and why?
Explain why Cu+ ion is not stable in aqueous solutions?
How is potassium dichromate prepared from chrome iron ore?
Explain why transition elements form alloys.
Electronic configuration of Mn2+ is ____________.
Read the passage given below and answer the following question:
The transition metals when exposed to oxygen at low and intermediate temperatures form thin, protective oxide films of up to some thousands of Angstroms in thickness. Transition metal oxides lie between the extremes of ionic and covalent binary compounds formed by elements from the left or right side of the periodic table. They range from metallic to semiconducting and deviate by both large and small degrees from stoichiometry. Since electron bonding levels are involved, the cations exist in various valence states and hence give rise to a large number of oxides. The crystal structures are often classified by considering a cubic or hexagonal close-packed lattice of one set of ions with the other set of ions filling the octahedral or tetrahedral interstices. The actual oxide structures, however, generally show departures from such regular arrays due in part to distortions caused by packing of ions of different size and to ligand field effects. These distortions depend not only on the number of d-electrons but also on the valence and the position of the transition metal in a period or group.
In the following questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices on the basis of the above passage.
Assertion: Transition metals form protective oxide films.
Reason: Oxides of transition metals are always stoichiometric.
The magnetic nature of elements depends on the presence of unpaired electrons. Identify the configuration of transition element, which shows highest magnetic moment.
Although fluorine is more electronegative than oxygen, but the ability of oxygen to stabilise higher oxidation states exceeds that of fluorine. Why?
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?
Assertion: The highest oxidation state of osmium is +8.
Reason: Osmium is a 5d-block element.
Answer the following question:
Which element of the first transition series has highest third ionisation enthalpy?
The element with atomic number 53 belongs to
The element with atomic number 46 belongs to
The orientation of an atomic orbital is governed by
Passing H2S gas into a mixture of Mn2+ and Ni2+, Cu2+, ions in an acidified aqueous solution precipitates.
Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other in:-
Which of the following ions has the maximum magnetic moment?
Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)
The trend of which property is represented by the following graph?
