Find the precise Ethanol Content of Gasoline by Forced Phase Separation

Place a sample of the gasoline in a graduated cylinder and add a given amount of water, shake well, let stand,  the water will combine with the ethanol and cause phase separation, the new water rich ethanol mixture will fall to the bottom of the cylinder.

Step by step method:

• Place 900 Ml of the gasoline in the Graduated Cylinder
• Add 100 Ml of fresh water to it
• Shake well
• Let rest for 15 Minutes ( or to full separation, indicated by clear gasoline )
•  Mark the precise level of the line separating the fluids
• We will call this level: LPV ( Lower Phase Volume )
• Note the exact LPV which will be used in the following formula:
  • % Ethanol in Gasoline = ( LPV – 100 ) / 900 X 100