We are talking about displacement.   Remember that mass equals volume multiplied by density.   When anything is placed in water, it floats when it displaces a volume of water equal in mass to its own mass before it is submerged.  It doesn't float if the volume it displaces has a mass less than its own mass. … Read more

in Water each molecule make 4 hydrogen bonds between molecules . but alcohol make 2 hydrogen bonds between molecules . so Alcohol Evaporates Faster Than Water .

Water is harder to break apart because of the hydrogen bonds between molecules where alcohols have hydrogen these hydrogen are more attracted to the oxygen in air rather than each other, where water hydrogen are attracted to the other oxygen in the other water molecules.