Drops of water form on the outer surface of a glass tumbler filled with ice-cold water. What causes these drops?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Water vapour in the air condenses on the cold surface
The air around the glass contains water vapour. When it touches the cold outer surface, it loses heat and changes back into liquid water. This change of vapour into liquid is called condensation.