how is it that water inside a sealed satchet leaks after being placed on a surface. Adeleke A?

Answer 1

Well, there could be microscopic holes in the plastic of the sachet, and when they meet a surface the surface-tension that was set up by the holes is compromised and the stuff leaks out.

Or maybe there is cold stuff in the sachet and then the warmth of the room makes it 'sweat' and appear to be leaking.

Or something else. Best I can do.