Why does it take several minutes for the smell of a freshly cut lemon to be detectable on the opposite side of the kitchen?

When the lemon is cut, it releases gaseous molecules into the surrounding air which are responsible for the lemon's smell. These molecules move slowly at room temperature and the distance that they must cover, in relevance to their size, is immense. These reasons contribute to the fact that the smell takes a while to reach the other side of the room.