Question

The concentration of a diluted "wine" sample was found to be 0.32 %(v/v) ethanol. Assuming the dilution was done as described in Part B of the procedure for this lab, what was the original concentration of ethanol in the "wine"? Enter your answer with 2 significant figures.

B. Preparation of Unknown Samples 1. Label two small test tubes "wine" and "breath”. 2. Use a disposable pipette, add 1.0 mL (25 drops) of “wine” solution to the wine test tube. a. Note, this "wine” solution has been diluted by a factor of 100 by the stockroom. 3. Use a disposable pipette, add 1.0 mL (25 drops) of “breath" solution to the breath test tube. 4. Using a new pipette, add 20 drops of sulfuric acid (H2SO4) to each small test tube. 5. Add 1 drop of chromic acid solution to each small test tube. Make sure the pipette you use has only been used for chromic acid. 6. Gently swirl the small test tubes until the contents are well mixed. 7. Place the small test tubes into the water bath and heat it for 5 minutes. 8. Promptly remove the small test tubes from the warm water bath and observe the color of the solutions. Which standard is the color of each solution closest to? Record your observations on the report sheet. 9. Discard the contents of all small test tubes into the appropriate waste container. 10. Discard the content of the large test tubes down the drain.

Answer 1

Here wine solution has been diluted by factor 100. So, Bilation factor (DF) = 100 in orginal concentration of ethano in cine - Concenration of ethanol in diluted water sample = 0.328% /w) x100' = 32% (Yv) (Answer) DE ater sample X