Question

7 why do gas molecules escape from the exosphere, but not other layers of the atmosphere?
a it is the layer farthest from earth, so there is less gravitational force
b it is the layer in the middle of the atmosphere, so there is higher pressure
c it is the layer where storms form, so winds carry gases away
d it is the layer closest to earth, so the gases dissolve in ocean water

8 why is the sky blue?
a most of the light from the sun is blue
b it reflects the color of the oceans
c blue light is most likely to be scattered by the atmosphere
d blue light is most likely to be absorbed by the atmosphere

9 which statement about temperature and altitude in the atmosphere is true?
a layers closer to the sun are warmer
b layers closer to earth are warmer
c altitude alone does not determine temperature
d the entire atmosphere is the same temperature

Explanation:

• Question 7: The exosphere is the outermost layer of the atmosphere. Gravitational force decreases with distance from Earth. Since the exosphere is farthest from Earth, gas molecules there experience less gravitational pull and can escape.
• Question 8: The sky appears blue because of Rayleigh scattering. Blue light has a shorter wavelength and is more likely to be scattered by the gas molecules and particles in the atmosphere.
• Question 9: Temperature in the atmosphere is not solely determined by altitude. Different layers have different temperature profiles due to various factors like absorption of solar radiation, heat transfer mechanisms, etc.

Answer:

• Question 7: A. It is the layer farthest from Earth, so there is less gravitational force
• Question 8: C. Blue light is most likely to be scattered by the atmosphere
• Question 9: C. Altitude alone does not determine temperature