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प्रश्न
Assertion: The highest oxidation state of osmium is +8.
Reason: Osmium is a 5d-block element.
पर्याय
Both assertion and reason are true, and reason is the correct explanation of the assertion.
Both assertion and reason are true but reason is not the correct explanation of assertion.
Assertion is not true but reason is true.
Both assertion and reason are false.
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उत्तर
Both assertion and reason are true but reason is not the correct explanation of assertion.
Explanation:
Osmium has the capacity to expands its octet by utilising all the electrons from its 6s and 5d orbitals this results it attaining an oxidation state of +8.
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संबंधित प्रश्न
Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{( aq)}}\] ion (Z = 27).
Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?
What may be the stable oxidation state of the transition element with the following d electron configuration in the ground state of its atom?
3d3
For M2+/M and M3+/M2+ systems, the E° values for some metals are as follows:
| Cr2+/Cr | −0.9 V |
| Mn2+/Mn | −1.2 V |
| Fe2+/Fe | −0.4 V |
| Cr3/Cr2+ | −0.4 V |
| Mn3+/Mn2+ | +1.5 V |
| Fe3+/Fe2+ | +0.8 V |
Use this data to comment upon:
- The stability of Fe3+ in acid solution as compared to that of Cr3+ or Mn3+ and
- the ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Electronic configurations
How would you account for the following?
Transition metals and their compounds act as catalysts.
The paramagnetic character in the 3d-transition series elements increases up to Mn and then decreases.
Electronic configuration of a transition element X in +3 oxidation state is [Ar]3d5. What is its atomic number?
Which of the following statements is not correct?
Which of the following will not act as oxidising agents?
(i) \[\ce{CrO3}\]
(ii) \[\ce{MoO3}\]
(iii) \[\ce{WO3}\]
(iv) \[\ce{CrO^{2-}4}\]
When a brown compound of manganese (A) is treated with \[\ce{HCl}\] it gives a gas (B). The gas taken in excess, reacts with \[\ce{NH3}\] to give an explosive compound (C). Identify compounds A, B and C.
Ionisation enthalpies of Ce, Pr and Nd are higher than Th, Pa and U. Why?
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.
Which of the following statements is not correct?
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)
Which property of transition metals enables them to behave as catalysts?
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.
Decide which of the following atomic numbers are the atomic numbers of the inner transition elements:
29, 59, 74, 95, 102, 104
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Oxidation states
The E° value for the Mn2+/Mn2+ couple is more positive than that of Cr3+/Cr2+ or Fe3+/Fe2+ due to the change of:
