JEE MAIN - Chemistry (2023 - 6th April Morning Shift - No. 12)

Strong reducing and oxidizing agents among the following, respectively, are :

$$\mathrm{Ce}^{4+}$$ and $$\mathrm{Eu}^{2+}$$

$$\mathrm{Eu}^{2+}$$ and $$\mathrm{Ce}^{4+}$$

$$\mathrm{Ce}^{4+}$$ and $$\mathrm{Tb}^{4+}$$

$$\mathrm{Ce}^{3+}$$ and $$\mathrm{Ce}^{4+}$$

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 $\mathrm{Ce}^{4+}$.