Ground vs. Excited State

1. Ground vs. Excited State • Ground State – electrons are in positions of lowest energy possible (normal) • Excited State – electron is in a temporary position of higher energy than ground state • Very unstable; the electron quickly returns to the ground state

2. Compared to a sodium atom in the ground state, a sodium atom in the excited state must have iRespond Question Multiple Choice F There is not change in the number of electrons, just their location A.) a greater number of electrons B.) a smaller number of electrons C.) an electron with greater energy D.) an electron with less energy E.)

3. Recognizing Ground Vs. Excited • Am I Excited!? • 1s22s22p5 • 1s22s12p5 • 1s22s22p63s23p63d4 • 1s22s22p63s23p64s1 • 1s22s22p63s23p64s23d6 • 1s22s22p63s23p64s23d105s1 G A = Ground B = Excited E E G G E

4. Which electron configuration is possible for a nitrogen atom in the excited state? iRespond Question Multiple Choice F A.) 1s22s22p3 Ground B.) 1s22s22p23s1 C.) 1s22s22p4 Oxygen D.) 1s22s22p2 Carbon E.)

5. Which electron configuration represents a potassium atom in the excited state? iRespond Question Multiple Choice F A.) 1s22s22p63s23p3 Phosphorous B.) 1s22s22p63s13p4 Excited Phosphorous C.) 1s22s22p63s23p64s1 Chlorine D.) 1s22s22p63s23p54s2 E.)

6. Changes in Electron Energy • Electrons must gain energy to transition to the excited state • Electrons release energy transitioning back to the ground state Ground  Excited e- gains energy Excited  Ground e- releases energy Be

7. Which electron transition represents a gain of energy? iRespond Question Multiple Choice F The farther from the nucleus the greater the energy A.) from 2nd to 3rd shell B.) from 2nd to 1st shell C.) from 3rd to 2nd shell D.) from 3rd to 1st shell E.)

8. Emission of Energy 1 • All elements have a unique energy level system (due to differences in nuclear charge) • The amount of energy released when returning from excited state to ground state is different for each element • Multiple transitions are possible • Some of the energy released has wavelengths within the visible light range

9. Atomic Spectra 1 • If the light emitted by an electron is passed through a prism it produces an atomic emission spectrum • The results are lines of light at specific energy levels • The atomic spectra of a given element is unique and can be used to identify an element

10. Na K Ca Cu Ba

11. The characteristic bright-line spectrum of an element occurs when electrons iRespond Question Multiple Choice F A.) move from lower to higher energy levels B.) move from higher to lower energy levels C.) are lost by a neutral atom D.) are gained by a neutral atom High to low releases energy E.)

12. The characteristic spectral lines of elements are caused when electrons in an excited atom move from iRespond Question Multiple Choice F A.) lower to higher energy levels, releasing energy B.) lower to higher energy levels, absorbing energy C.) higher to lower energy levels, releasing energy D.) higher to lower energy levels, absorbing energy E.)

13. Electron X can change to a higher energy level or a lower energy level. Which statement is true of electron X? iRespond Question Multiple Choice F A.) Electron X emits energy when it changes to a higher energy level. B.) Electron X absorbs energy when it changes to a higher energy level. C.) Electron X absorbs energy when it changes to a lower energy level. D.) Electron X neither emits nor absorbs energy when it changes energy level. E.)

14. Which of the following quantum leaps would be associated with the greatest energy of emitted light? iRespond Question Multiple Choice F A.) n = 5 to n = 1 B.) n = 4 to n = 5 C.) n = 2 to n = 5 D.) n = 5 to n = 4 E.)

15. The atomic emission spectra of a sodium atom on Earth and of a sodium atom in the sun would be iRespond Question Multiple Choice F A.) the same B.) different from each other C.) the same as those of several other elements D.) the same as each other only in the ultraviolet range Each element has a unique spectra that is unchanged based on locations E.)

16. Which two elements are present in the unknown spectra below? iRespond Question Multiple Choice F A.) Li & H B.) Li & Na C.) H & He D.) Li & He E.)

17. Electron Cumulative Quiz • Electron Configurations: • Arrows • Shorthand spdf • Noble Gas • Bohr • Valence Electrons • Lewis Dot Diagrams • Ground Vs. Excited State • Bright Line Spectra