Kane walks into the bathroom after I had taken a shower, points to the mirror and says,
"Mom, why is it like that?"
Me: "The mirror fogged up because I took a hot shower."
Kane: "But why?"
Me: (I could tell he was in his "why" mood and was talking for the sake of talking so I decided to roll with it) "Well, some of the water from the shower gets hot enough that it evaporates, turning into a gas, we call it steam. The steam floats through the air and when it hits the mirror it cools down and goes through condensation, fogging up the mirror."
Kane: "What's condensation?"
Me: "When a vapor turns into a liquid."
Kane: "What kind of liquid?"
Me: "Well, this is water."
Kane: "Oh, well, who cares about all that, anyway."
Leaves bathroom shaking his head dismissively.