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प्रश्न
It is difficult to cook vegetables on hills and mountains. Explain the reason.
उत्तर
This is because at high altitudes atmospheric pressure is low; therefore, boiling point of water decreases and so it does not provide the required heat energy for cooking.
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संबंधित प्रश्न
A liquid can change into vapour state at a fixed temperature.
State the boiling point of water.
A certain quantity of water is heated from 20°C to 100°C. Its temperature is recorded after each 1 minute. The observations are:
| Time (in minute) | Temperature (in °C) |
| 0 | 20 |
| 1 | 30 |
| 2 | 40 |
| 3 | 50 |
| 4 | 60 |
| 5 | 70 |
| 6 | 80 |
| 7 | 90 |
| 8 | 100 |
| 9 | 100 |
| 10 | 100 |
| 11 | 100 |
| 12 | 100 |
How is the boiling point of water affected when some salt is added to it?
Assertion: The process of conversion of liquid water to its vapours by heating the liquid is called boiling.
Reason: The process of conversion of water vapours to liquid by cooling the vapours is called condensation.
During summer, water kept in an earthen pot becomes cool because of the phenomenon of
The boiling points of diethyl ether, acetone and n-butyl alcohol are 35°C, 56°C and 118°C respectively. Which one of the following correctly represents their boiling points in kelvin scale?
Why does the temperature of a substance remain constant during its melting point or boiling point?
We would have observed that the plate that covers the cooked food items has water droplets inside. Why? Explain.
Assertion (A): Burning of a candle is considered a physical as well as chemical change.
Reason (R): Melting of wax is a physical change melted wax turns into vapours and then bums which is a chemical change.
