A lemon juice cleans a penny. I believe this to be the answer because the lemon cleans the penny but no molecules change
Condensation is the change of water from its gaseous form (water vapor) into liquid water. Condensation generally occurs in the atmosphere when warm air rises, cools and looses its capacity to hold water vapor. As a result, excess water vapor condenses to form cloud droplets.
It can take 49 days, I could be wrong. What do you mean in this question?