The calomel electrode is commonly used as a reference electrode in electrochemical measurements. It consists of mercury (\( \text{Hg} \)) in contact with mercurous chloride (calomel, \( \text{Hg}_2\text{Cl}_2 \)) in a saturated potassium chloride (\( \text{KCl} \)) solution.
The calomel electrode falls under the category of "Metal – Insoluble Salt – Anion electrodes" because it involves a metal (\( \text{Hg} \)), an insoluble salt (\( \text{Hg}_2\text{Cl}_2 \)), and the chloride ions (\( \text{Cl}^- \)) in solution.
The correct answer is Option (1): Metal – Insoluble Salt – Anion electrodes.
Let one focus of the hyperbola $ \frac{x^2}{a^2} - \frac{y^2}{b^2} = 1 $ be at $ (\sqrt{10}, 0) $, and the corresponding directrix be $ x = \frac{\sqrt{10}}{2} $. If $ e $ and $ l $ are the eccentricity and the latus rectum respectively, then $ 9(e^2 + l) $ is equal to:
Let $ P_n = \alpha^n + \beta^n $, $ n \in \mathbb{N} $. If $ P_{10} = 123,\ P_9 = 76,\ P_8 = 47 $ and $ P_1 = 1 $, then the quadratic equation having roots $ \alpha $ and $ \frac{1}{\beta} $ is: