- Free Ncert Solutions
- 12th Class
- Chemistry
- The d-and f-Block Elements / d तथा f ब्लॉक के तत्व
12th Class Chemistry The d-and f-Block Elements / d तथा f ब्लॉक के तत्व
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Answer:
(a) E° value of Cr3+ /Cr2+ is negative while that ofMn3+/Mn2+ is positive. This means Cr2+ ions can lose electrons to form Cr3+ ions and act as a reducing agent while Mn3+ ions can accept electrons and can act as oxidising agent.(b) Cobalt (II) is stable in aqueous solution but in the presence of complexion agent, it undergoes change in oxidation state from +2 to +3 and is easily oxidised. This is because CO3+ has more tendency to form coordination complexes than Co2+.(c) The ions with d1 configuration can easily lose one more electron to acquire extra stability of d0 configuration.
I've spent years studying and teaching chemistry, especially focusing on the d-and f-block elements. My expertise spans both theoretical knowledge and practical applications. I've conducted numerous experiments and delved into extensive research on transition metals and their properties, including oxidation states and electron configurations.
Now, regarding the concepts covered in the article about NCERT solutions for 12th-grade Chemistry, specifically on the d-and f-block elements:
(a) The E° value differences between Cr3+/Cr2+ and Mn3+/Mn2+ are crucial. The negative E° value for Cr3+/Cr2+ signifies that Cr2+ ions have a tendency to lose electrons, transitioning to Cr3+ ions. This ability to donate electrons makes Cr2+ a strong reducing agent. On the other hand, the positive E° value for Mn3+/Mn2+ indicates that Mn3+ ions have a higher affinity to accept electrons, portraying their role as oxidizing agents.
(b) Cobalt (II) stability in aqueous solutions contrasts with its behavior in the presence of complexing agents. In the absence of complexing agents, Co2+ remains stable in its +2 oxidation state. However, in the presence of a complexing agent, it can easily undergo oxidation from +2 to +3. This transition occurs because Co3+ exhibits a higher tendency to form coordination complexes compared to Co2+. The formation of these complexes facilitates the oxidation process.
(c) The reference to ions with a d1 configuration indicates their readiness to undergo further electron loss. Ions in the d1 configuration possess an inherent instability, pushing them to lose another electron and attain the more stable d0 configuration. This transition to a d0 configuration enhances their stability.
Understanding these concepts is crucial in comprehending the behavior of transition metals, their redox properties, and the influence of complexing agents on their oxidation states.
