Passage Potassium permanganate (KMnO 4 ) is a highly reactive inorganic salt that appears as granular dark purple crystals, nearly black in color. Due to its useful chemical properties and the fact that its reactions typically do not produce compounds that are toxic, KMnO 4 is employed in a variety of applications, including use as a topical skin disinfectant, an antifungal agent, a fire starter, and a disinfectant for drinking water.KMnO 4 is widely used as an alternative water treatment agent both to disinfect drinking water and to remove undesirable dissolved iron and sulfur compounds. The crystals are highly soluble in water and form bright pink aqueous solutions that provide a visual indication of the presence of KMnO 4 treatment residual. As a drinking water disinfectant, a KMnO 4 concentration of 1 mg/L is recommended unless higher levels of contamination are indicated by the absence of a pink residual.Industrial production of potassium permanganate is accomplished in two steps. In step 1, manganese(IV) oxide (MnO 2 ) is heated with potassium hydroxide in the presence of oxygen to produce potassium manganate (K 2 MnO 4 ), as outlined in Reaction 1.2 MnO 2 + 4 KOH + O 2 → 2 K 2 MnO 4 + 2 H 2 OReaction 1In step 2, the potassium manganate is then converted into potassium permanganate electrochemically according to Reaction 2.2 K 2 MnO 4 + 2 H 2 O → 2 KMnO 4 + 2 KOH + H 2 Reaction 2 -Suppose 0.80 L of 3.0 M aqueous K₂MnO₄ is combined with 0.20 L of 2.0 M aqueous KMnO₄ to make a solution. What is the concentration of potassium ions in the solution?

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11ecba2d_11da_d038_a3bf_53007e2da394_MD0008_00 When a given volume is dispensed from a stock solution, a specific number of moles of solute are transferred with the sample. The number of moles in the sample can be calculated by multiplying the molarity (mol/L) of the stock solution by the volume (L) of the sample. When two samples from different stock solutions are mixed, the final molar concentration of the sample mixture is determined by the total number of moles transferred (of a given species) divided by the total volume of the resulting mixture. For the K₂MnO₄ stock solution, a 0.80 L sample transfers 4.8 mol of K⁺ ions, and for the KMnO₄ stock solution, a 0.20 L sample transfers 0.4 mol of K⁺ ions. When the samples are mixed, a total of 5.2 mol of K⁺ ions (4.8 mol + 0.4 mol) are present in a mixture volume of 0.80 L + 0.20 L = 1.00 L. Therefore, the concentration of K⁺ ions resulting from mixing the samples is 5.2 mol/L. (Choice A) If a 1:1 mole ratio is used instead of the 2:1 mole ratio of K⁺ ions to K₂MnO₄ present in the potassium manganate solution, 2.8 M is obtained from the calculation. (Choice B) The average K⁺ ion concentration in the two stock solutions is 4.0 M. Because unequal volumes from the two stock solutions are mixed, the average concentration of the stock solutions is not equivalent to the concentration of the mixture. (Choice D) The K⁺ ion concentration in the K₂MnO₄ stock solution is 6.0 M. The 2:1 mole ratio between K⁺ ions and K₂MnO₄ makes the K⁺ ion concentration double that of the K₂MnO₄ concentration. Educational objective: The number of moles transferred in a sample taken from a stock solution can be calculated by multiplying the molarity of the stock solution by the sample volume. When two samples from different stock solutions are mixed, the molarity of the sample mixture equals the total number of moles transferred divided by the total mixture volume.

Passage Potassium Permanganate (KMnO4) Is a Highly Reactive Inorganic Salt That

Passage Potassium Permanganate (KMnO₄) Is a Highly Reactive Inorganic Salt That