Question

Give reasons for the following observation:
The smell of hot sizzling food several metres away, but to get the smell from cold food you have to go close.

Answer 1

Hint: You must have noticed when you enter your home when something delicious is being cooked, you can smell it from far away. But when you take out food from the refrigerator it doesn’t give any smell, you have to go closer to smell it.

Complete step by step solution:

The average kinetic energy of gas particles is directly proportional to the absolute temperature of the gas, and all gases at the same temperature possess the same average kinetic energy.
Now, in the given question, the particles of hot sizzling food possess large kinetic energy and diffuse in air rapidly and can reach several metres away easily. At higher temperature, particles have high kinetic energy and move faster hence, the particles of hot vapours from hot food move faster.
Similarly, if we consider the particles of cold food possess less kinetic energy and are not able to reach several metres away At lower temperature, particles have low kinetic energy and they move slowly. Therefore, the particles in cold food have low kinetic energy due to low temperature.
Due to the following factors of kinetic energy and temperature the smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close.

Note: Molecules in the solid phase have the least amount of energy as the particles are not allowed to move freely, while gas particles have the greatest amount of energy, liquid being an intermediate of the two.