How can phospholipids form a film when mixed in water?

Question

How can phospholipids form a film when mixed in water?

Answer 1

The "heads" are hydrophilic (they like water). The "tails" are hydrophobic (they want to get away from water).

So when put into water they form a bi-membrane. A 2 layered sheet with the heads pointing outwards and the tails pointing inwards.