Physics Q's?

Question

Driving a car raises temperature of the tyres.
This causes the pressure of the air in the tyres to increase.
Why is this?
A Air molecules break up to form separate atoms.
B Air molecules expand with the rise in temperature.
C The force between the air molecules increases.
D The speed of the air molecules increases.

To mark a temperature scale on a thermometer, fixed points are needed.
Which is a fixed point?
A The bottom end of the thermometer
B The top end of the thermometer
C The temperature of pure melting ice
D The temperature of pure warm water

4a) State two differences between evaporation of water and boiling of water.
b) The specific latent heat of vaporization of water is 2250 kJ/kg.
Explain why this energy is needed to boil water and why the temperature of the water does not change during the boiling.

Please answer the question. I don't need any of your comments.

Answer 1

D The speed of the air molecules increases

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C The temperature of pure melting ice

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Evaporation occurs at the surface of water. Boiling can occur in the volume of the water.

When boiling the vapor pressure of water equals the ambient pressure. That is not necessary for evaporation.

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It is the energy needed to transform a liquid into a gas by overcoming the intermolecular interactions.

Energy applied to the liquid goes to converting the liquid to a gas. For a liquid at the boiling point, any additional energy vaporizes the liquid rather than raising its temperature.

Answer 2

1D
2C

4a in evaporation, you don't get water in gaseous form (steam), there are only single molecules mixing with air. When you boil water, you get water as a gas.

4b In a fluid, there are forces between the molecules which hold them together. In steam, the molecules are floating free. To break the "bonds" which hold the molecules together, you need energy. The temperature of water does not rise during boiling, because the heat energy you aplly to the water is absorbed by either a "water" moleule or a "steam" molecule. If it was a "water" molecule, the energy is used to break the bond to other molecules, and so our m. doesn't get faster. If it is a freely moving molecule (steam), it gets faster, it hits a water drop, and its energy is used to break bonds in the water drop, but the molecule itself gets slow again. So no molecule gets faster while there are bonds to break, and the temperature doesn't rise.

Answer 3

See, I was gonna give you the answers for the first 2, but your snooty comment about not needing comments really turned me off, so all you get is a comment.

Answer 4

well i only know the 4a Q.
Evaporation occures at any temperature.
while boiling occurs at 100'C for water