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potassium dichromate also called potassium bichromate is an orange red crystalline solid k2cr2o7 soluble in water and inso

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Potassium dichromate, also called potassium bichromate, is an orange-red crystalline solid, K2Cr2O7, soluble in water and insoluble in alcohol. What is the molar concentration of this salt in a solution whose chromium ion concentration is 5.72 mg/mL? Data: K=39; Cr=52 and O=16 g/mol. NOTE: The answer must have 3 places after the comma, to avoid rounding errors.

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Answer to a math question Potassium dichromate, also called potassium bichromate, is an orange-red crystalline solid, K2Cr2O7, soluble in water and insoluble in alcohol. What is the molar concentration of this salt in a solution whose chromium ion concentration is 5.72 mg/mL? Data: K=39; Cr=52 and O=16 g/mol. NOTE: The answer must have 3 places after the comma, to avoid rounding errors.

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\text{Concentração de íons crômio em g/L} = 5.72 \times 10^{-3} \, \text{g/mL} \times 1000 \, \text{mL/L}

\text{Concentração de íons crômio em g/L} = 5.72 \, \text{g/L}

\text{Massa molar de } Cr = 52 \, \text{g/mol}

\text{Número de mols de } Cr = \frac{5.72 \, \text{g/L}}{52 \, \text{g/mol}}

\text{Número de mols de } Cr = 0.110 \, \text{mol/L}

K_2Cr_2O_7 \rightarrow 2K^+ + 2Cr^{3+} + 7O^{2-}

[Cr^{3+}] = 2 [K_2Cr_2O_7]

0.110 \, \text{mol/L} = 2 [K_2Cr_2O_7]

[K_2Cr_2O_7] = \frac{0.110}{2} \, \text{mol/L}

[K_2Cr_2O_7] = 0.055 \, \text{mol/L}

\text{Answer: } 0.055 \, \text{mol/L}

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