Chromium often is electroplated on other metals and even plastics to produce a shiny metallic appearance.How many grams of chromium would plate out from a solution of Cr(NO₃)₃ when 10.0 amps of current are passed through the electrolytic cell for 5.36 hours?

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First, convert the time from hours to seconds: 5.36 hours * 3600 seconds/hour = 19296 seconds. The charge passed through the cell is current * time = 10.0 amps * 19296 seconds = 192960 coulombs. The molar mass of chromium is approximately 52.0 g/mol, and it has a valency of 3 (as suggested by the oxidation state in the given compound). Using Faraday's second law of electrolysis, the amount of chromium deposited can be calculated using the formula: mass = (Molar mass * Charge) / (n * F), where n is the number of electrons (valency, which is 3 for chromium in this case) and F is Faraday's constant (96485 C/mol). Substituting the values: mass = (52.0 g/mol * 192960 C) / (3 * 96485 C/mol) = 34.7 g.

Chromium Often Is Electroplated on Other Metals and Even Plastics