Purification of chromium can be achieved by electrorefining chromium from an impure chromium anode onto a pure chromium cathode in an electrolytic cell. how many hours will it take to plate 13.5 kg of chromium onto the cathode if the current passed through the cell is held constant at 30.0 a ? assume the chromium in the electrolytic solution is present as cr 3 +.

696 h

Explanation:

Let's consider the reduction of Cr³⁺.

Cr³⁺(aq) + 3e⁻ → Cr(s)

We can establish the following relations.

How many hours will it take to plate 13.5 kg of chromium onto the cathode if the current passed through the cell is held constant at 30.0 A?

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.