Question

Cesium has the lowest ionization energy of all the elements. 3-1 a) Explain why. (Don't just cite the periodic trends. Make sure you give a chemical explanation for this property.) b) What is the wavelength of a photon that could ionize a Cs atom? What region of the electromagnetic spectrum does this light belong to?

45.5kJ/mol-1

Answer 1

Page 2 – continuedaran. wavelength, do the = (6.62681034) & (2.9979x108mst? 7.555 X 10 20 = 16.62682.9979 x 10 34x108x1020 - 2.629 x 10 Id = 2629X106 m * Near infrared (NIR) begins just reel portion of the electromagnetic Spectrum. : 0.7 um - 3 um = Near inferer Red. As, Cs photon coquelength is 2.629x106m2 2,629 m. Belongs to the Near in fra Red region.

Answer: Page ) Cesium (Cs) has the lowest ionization energy of all the elements Tonization energy means minimum amount of energy required to remove the most loosely bound electron, the valence dechran of an isolate del neutral gaseous atom or molecule If we see the trend in periodic table, its observed that Lonization energy goes on increasing it w from left to right Megroup 14018) of periodic table, Thus, alkali metals baning less ionization energy because ir they loose electron they get the electronic configurabon of nobel gas ( which is most stable).. Thus, election present in Cesium Colin 6th shell, the more electrons. Shielding the outer shell from the hudeus, the less energy required to expel an election from said atom .: Cs is said to have lowest ponization energy, (6) Given that the ionization energy of cesium is 45.5kJ/molt. The waveleng tid, of a photon supplying energy, &, 1J . dohc here, ha 6Q6 8 10 34 Is (Plank's constant E C2 2.99798108 mst' (speed of light) Given, E = 455 kJ/molt noc convert this value from les molt to Satom? E 37-45.5 (CJ molte 45.5 kJ molt (19005) * ( motsation = 7.555 x 103 - 7.55S X 108x1023 = 7.555X1020 Jatomt - 1023 wavelength of photon, do res he