Question

We are able to smell cooked food from a distance. Which property of matter does it reflect?
A. The particles move faster at lower temperature.
B. The particles of matter are continuous.
C. Particles of different matters have different forces of attraction.
D. Particles of matter can mix with each other.

Answer 1

Hint: Cooked food releases certain gases that gas particles spread out which leads to spreading out the aroma of the food from a distance as those gas particles carry the smell. We know that gases have certain properties such as expandability, compressibility and diffusibility.

Complete answer:
Let us discuss how these properties help in carrying out the phenomenon. Gases have limitless expandability. They expand to fill the entire vessel they are placed in and take the shape and volume of the vessel, similarly the gases full of aroma that the cooked food releases expand to fill the entire room. Diffusibility or diffusion is another property which is the main reason for this phenomenon to occur, which means that gases have a tendency to mix with one another spontaneously and form a homogeneous mixture. It could occur against gravity even. Hence the mixing ability of gases is known as diffusion.
Kinetic theory of gases is proposed for gases which states that Gas molecules are in constant random motion with high velocities. Gases move freely and independent of each other.
At high temperature they obtain kinetic energy and move with a higher velocity.

Therefore we can conclude that the correct option is D.

Note: Diffusion and effusion are the two phenomena of gases explained under graham's law which states that at constant pressure and temperature, the rate of diffusion and effusion of a gas is inversely proportional to the square root of its density.