Determine the percent composition of potassium dichromate, K₂Cr₂O₇. A)17.5% K, 46.6% Cr, 35.9% O B)29.8% K, 39.7% Cr, 30.5% O C)36.5% K, 48.6% Cr, 14.9% O D)37.2% K, 24.7% Cr, 38.1% O E)None of these choices are correct.

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The formula for potassium dichromate is K2Cr2O7. To find the percent composition, calculate the molar mass of the compound and then find the mass percentage of each element. The molar mass of K2Cr2O7 is approximately 294.185 g/mol (K=39.1*2, Cr=52.0*2, O=16.0*7). The percent composition is calculated as follows: K: (78.2/294.185)*100 ≈ 26.6%, Cr: (104/294.185)*100 ≈ 35.3%, O: (112/294.185)*100 ≈ 38.1%. None of the choices match these calculations.

Determine the Percent Composition of Potassium Dichromate, K2Cr2O7

Determine the Percent Composition of Potassium Dichromate, K₂Cr₂O₇