Question

q4. uvb light is partly blocked by the ozone layer but otherwise pass through the atmosphere because:
a) uvb photons have enough energy to break the bond in o₂ but not the bonds in o₃.
b) uvb photons do not have enough energy to break bonds in either o₃ or o₂.
c) uvb photons have enough energy to break the bonds in both o₂ and o₃.
d) uvb photons have enough energy to break bonds in o₃ but not the bond in o₂.
q5. what kind of em radiation is associated with food heating, communications with satellites, emitted by rotating molecules, and has waves from mm to 30 cm in length?
a) radiowaves.
b) x - radiation.
c) microwaves.
d) gamma rays.
q6. the (incorrect) prediction for emission from blackbodies, known as the “uv catastrophe” showed that:
a) as wavelength decreases, there is a gentle rise in intensity, then a peak followed by a rapid drop.
b) as wavelength decreases, there is a steady increase in emission intensity.
c) as wavelength increases, there is a gentle rise in intensity, then a peak followed by a rapid drop.
d) as wavelength increases, there is a steady increase in emission intensity.

Explanation:

Q4:

UVB photons have enough energy to break the bonds in ozone ($O_3$) but not in oxygen ($O_2$), which is why the ozone layer can partly block UVB.

Q5:

Microwaves are used for food - heating (microwave ovens), satellite communications, and are emitted by rotating molecules, with wavelengths ranging from mm to 30 cm.

Q6:

The UV - catastrophe was the incorrect prediction that as the wavelength of radiation from a blackbody decreases, the emission intensity steadily increases, which was in contrast to experimental results.

Answer:

Q4. d
Q5. c
Q6. b