(a) Coconut oil is in liquid state. In winter the surrounding temperature / atmospheric temperature starts decreasing.
Coconut oil starts cooling or losing heat, it changes to solid state.
Thus,
Coconut oil thickens in winter.
(b) When kerosene is left open in a dish, it is exposed to surrounding temperature.
As the temperature is more, kerosene starts continuously evaporating and finally disappears.
(c) The fragrance of incense sticks is given out in the form of scented vapours.
As vapours are in gaseous state, the gas molecules spread out in the room.
The molecules of gas move very fast and there are no forces to stop them from going apart.
Therefore the fragrance of incense sticks lighted in one corner of room spreads to the other corner.
(d) The mass of plastic ball is less than an apple. This difference is because of their densities.
Since an apple has greater density, it will sink to the bottom on other hand the plastic ball has lesser density, it will float over water surface.
