Question

Question 16 5 pts Use the Bohr model to find the second longest wavelength of light in the Paschen series for a triply-ionized Be atom (Z - 4). Recall that the Paschen series corresponds to transitions to the second excited state in = 3). 13.5 nm O 117 nm O 73.0 nm 41.1 nm O 80.2 nm Question 17 5 pts Light with a wavelength of 137 nm is shined on the surface of potassium metal. Photoelectrons are ejected from the metal's surface. What is the maximum speed of the ejected photoelectrons? The work function of potassium metal is 2.30 eV. 07.15E5 m/s 0 #51E6 TỰs 6.32E5 m/s O 8.99E5 ms 1.54E6 m/s

Answer 1

16) = R22 1.097 tlom - Ridburg constant a n = 3 For longest wavelength na=4 ļ= 1.097410 x 42 42/ 32 -] 117 nm Incident light energy E=hc ब E = 9.oslen 1240 eura 137 na [bc= 664 +1-74 & 3x 10 _1240ernm wowork function -2.3 eu 1.6xlola wt K. E (K. El max E-w=9.051. -2.3=6.75lev Elmax IEVE 1.6+ 10-19 J = 10.801 t 1619 (K. Emas 6.7514 16+1019 mass of electron m= 9.1x lo- LK & max 31 alk. E) max 2x lo. 8o14 1519 9,1X10 31 Va 1.54 x 10 loomis