Answer:
because ethanol is polar
Step-by-step explanation:
polar dissolves in polar. Ethanol has a hydroxyl(-OH) functional group in it.
Due to the presence of a bond between electronegative atom oxygen and hydrogen, the O-H bond acquires polarity.
Hence, due to the presence of polarity in O-H bond, it forms a Hydrogen bond with water which is responsible for the responsibility of ethanol in water.