Alcohol level in blood is determined by the reaction with `K_2Cr_2O_7` solution in acidic medium. Calculate the blood level in mass percent if 10 " mL of " 0.05 M solution of `K_2Cr_2O_7` is required for the reaction of a 10.0 g sample of blood.

Explanation

To solve the problem of determining the alcohol level in blood in mass percent, we will follow these steps:

### Step 1: Write the Balanced Reaction
The reaction between ethanol (C2H5OH) and potassium dichromate (K2Cr2O7) in acidic medium can be written as:
\[ C_2H_5OH + 2Cr_2O_7^{2-} + 16H^+ \rightarrow 2CO_2 + 4Cr^{3+} + 11H_2O \]

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