Electromagnectic waves: Photons?

Question

1) When sodium atoms are excited (for example, by heating salt in a flame) they emit bright yellow light at two wavelengths of 589.0 nm and 589.6 nm. That emission implies that the sodium atom has two nearby energy levels separated by only
A) 2 eV
B) none of these
C) 0.6 eV
D) 0.6 MeV
E) 2 10-3 eV

2) Which statement is NOT true for a photon?
A) none of these
B) it is electromagnetic in nature
C) it always travels at the speed c independent of frequency
D) it has wavelike properties
E) it possesses energy independent of frequency

3) Determine the vacuum wavelength, frequency, and energy in Joules of a 2.50 eV photon. What type of radiation is it?

Answer 1

1: E

2: E

3:
2.5 eV = 495.936 nm =
604.497 THz = 4.00547925E-19 J

so visible light...blue-green actually.