8. Gases have definite volume but do not have a definite shape.
9. Water at 100°C has more heat energy than steam at 100°C.
10. Water releases 80 calories of heat per gram during freezing into ice at 0°C.
11. Evaporation takes place at all temperatures.
12. In the presence of wind, the rate of evaporation increases.
13. The process of a gas converting directly into a solid is called sublimation.
14. Common salt undergoes sublimation.
Answers
Answer:
all the statements are true
Answer:
8. false
9. false
10. false
11. true
12. true
13. false
14. true
Explanation:
8. false. Because gases have both definite shape and volume
9. false, Because steam includes the latent heat of vapourisation. As a result, the energy in a kilogram of steam at 100 deg C is 2257 kJoules more than that in a kilogram of water at 100 deg C.
10. If 1 g of water is given 2 calories, its temperature will go up 2 degrees. Melting ice at 0 degrees Celsius: It takes 80 calories to melt 1 gram of ice. If 1 g of ice (at 0 degrees Celsius) is given 80 calories, it will melt and the final temperature of the water will be 0.
11. it's true, yes, evaporation can take place at temperature
12. it's also true that In the presence of wind, the rate of evaporation increases.
13. False, because such process is known as deposition, and sublimation is the process by which a substance directly changes from solid state to gaseous state at a fixed temperature.
14. it's true that common salt undergoes sublimation