How many grams of chromium metal are plated out when a constant current of 8.00 A is passed through an aqueous solution containing Cr³⁺ ions for 320.minutes? A)27.6 g B)49.2 g C)82.4 g D)248 g

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Quizplus · Accepted Answer

The amount of chromium plated out can be calculated using Faraday's laws of electrolysis. The mass of a substance deposited at an electrode is directly proportional to the amount of electric charge passed through the electrolyte. The formula to calculate the mass is $m = \frac{ItM}{nF}$, where $m$ is the mass of the substance (in grams), $I$ is the current (in amperes), $t$ is the time (in seconds), $M$ is the molar mass of the substance (in g/mol), $n$ is the number of electrons transferred in the reaction, and $F$ is Faraday's constant ($96485 C/mol$).Given:- $I = 8.00 A$- $t = 320 \text{ minutes} = 320 \times 60 \text{ seconds}$- $M$ for chromium ($Cr$) is approximately $52 g/mol$- $n = 3$ (since chromium goes from a $+3$ charge in $Cr^{3+}$ to $0$ in the metal form)Plugging these values into the formula:$$m = \frac{8.00 \times (320 \times 60) \times 52}{3 \times 96485}$$$$m \approx 27.6 g$$Therefore, 27.6 grams of chromium metal are plated out.

How Many Grams of Chromium Metal Are Plated Out When