JEE Main 2023 — D And F Block Elements Question with Solution

Strong reducing agents are those that readily donate electrons, and strong oxidizing agents are those that readily accept electrons.

• ${\mathrm{Ce}}^{4+}$: It can accept an electron to form ${\mathrm{Ce}}^{3+}$, so it is a strong oxidizing agent.


• ${\mathrm{Eu}}^{2+}$: It can donate an electron to form ${\mathrm{Eu}}^{3+}$, so it is a strong reducing agent.

So the correct answer is: ${\mathrm{Eu}}^{2+}$ and ${\mathrm{Ce}}^{4+}$.