Advertisements
Advertisements
प्रश्न
Why does our palm feel cold when we put some acetone or petrol or perfume on it?
Advertisements
उत्तर
- When we put some acetone or petrol or perfume on our palm, it evaporates.
- During evaporation, particles of the liquid absorb energy from the surrounding or the surface of the palm to compensate for the loss of energy, making the surroundings cool.
- Hence, our palm feels cold when we put some acetone or petrol or perfume on it.
APPEARS IN
संबंधित प्रश्न
A liquid can change into vapour state at all temperatures.
Wet clothes dry more quickly on a warm dry day than on a cold humid day. Explain.
Why is cooling produced on evaporation of a liquid?
Explain with an example to demonstrates that when a liquid evaporates, it takes heat from its surroundings.
Define the following term Freezing.
Why does all the water of the earth not get evaporated during hot summer days ?
The scientists now say that there are actually five states of matter A, B, C, D and E. The state A has a fixed volume but no fixed shape. The state B can be compressed very easily by applying pressure and state C has a fixed shape as well as a fixed volume. The state D is a mixture of free electrons and ions whereas state E is named after an Indian scientist and a famous physicist.
- Name the physical states (i) A (ii) B (iii) C (iv) D, and (v) E
- Name one substance belonging to state C which can directly change into vapours on heating. What is this process known as ?
- Name one substance which normally belongs to state B but whose solid form changes directly into gaseous state.
- Name the most common substance belonging to state A.
- Which state of matter makes the sun and other stars to glow ?
The ______ of air is dependent on the temperature of air.
How is humidity measured?
Look at Fig. 1.3 and suggest in which of the vessels A,B, C or D the rate of evaporation will be the highest? Explain.

