ground vs. excited state ground state – electrons are in positions of lowest energy possible...

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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

Compared to a sodium atom in the ground state, a sodium atom in the excited state must have

A.) a greater number of electrons

B.) a smaller number of electrons

C.) an electron with greater energy

D.) an electron with less energy

There is not change in the number of electrons, just their location

Recognizing Ground Vs. Excited

Am I Excited!? 1s22s22p5

1s22s12p5

1s22s22p63s23p63d4

1s22s22p63s23p64s1

1s22s22p63s23p64s23d6

1s22s22p63s23p64s23d105s1

A = Ground

B = Excited

GE

EGGE

Which electron configuration is possible for a nitrogen atom in the excited state?

A.) 1s22s22p3

B.) 1s22s22p23s1

C.) 1s22s22p4

D.) 1s22s22p2

Ground

Oxygen

Carbon

Which electron configuration represents a potassium atom in the excited state?

A.) 1s22s22p63s23p3

B.) 1s22s22p63s13p4

C.) 1s22s22p63s23p64s1

D.) 1s22s22p63s23p54s2

Phosphorous

Excited PhosphorousChlorine

Changes in Electron Energy

Electrons must gain energy to transition to the excited state

Electrons release energy transitioning back to the ground state Be

Ground Excited

e- gains energy

Excited Ground

e- releases energy

Which electron transition represents a gain of 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

The farther from the nucleus the greater the energy

Emission of Energy 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

Atomic Spectra 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

Ca

Na

Ba

Cu

K

The characteristic bright-line spectrum of an element occurs when electrons

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

The characteristic spectral lines of elements are caused when electrons in an excited atom move from

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

Electron X can change to a higher energy level or a lower energy level. Which statement is true of electron X?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.

Which of the following quantum leaps would be associated with the greatest energy of emitted light?

A.) n = 5 to n = 1

B.) n = 4 to n = 5

C.) n = 2 to n = 5

D.) n = 5 to n = 4

The atomic emission spectra of a sodium atom on Earth and of a sodium atom in the sun would be

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

Which two elements are present in the unknown spectra below?

A.) Li & H

B.) Li & Na

C.) H & HeD.) Li & He

Electron Cumulative Quiz Electron Configurations:

Arrows Shorthand spdf Noble Gas Bohr

Valence Electrons Lewis Dot Diagrams Ground Vs. Excited State Bright Line Spectra

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