Electron Binding Energies

Question 1

Atom

Answer 1

Smallest particle that has all the properties of an element

Question 2

Three fundamental particles of an atom

Answer 2

• proton
• neutron
• electron

Question 3

Nucleus ____ of the atom

Answer 3

• center of the atom
• contains protons and neutrons
• electrons surround the nucleus in various orbits

Question 4

Isotope

Answer 4

• atoms have same number of protons in nucleus

- different number of neutrons (results in different atomic mass)

Question 5

Ion

Answer 5

-atom that gains or loses electrons

Question 6

Charge

Answer 6

• neutral (normal state of an atom, # of protons= # electrons
• ionization: when an atom gaines or loses and electron

Question 7

K shell is closest to the _____

Answer 7

Nucleus

Question 8

How do electrons maintain orbit?

Answer 8

• centrifugal force

- centripetal force

Question 9

Binding energy

Answer 9

• defined as the strength of the attachment of an electron to the nucleus
• the CLOSER an electron is to the nucleus, the HIGHER the binding energy
• meaning: more energy required to remove a K shell electron vs an M shell electron

Question 10

Binding energy depends on 2 things:

Answer 10

• ATOMIC # OF THE ATOM (the HIGHER the atomic #, the HIGHER the binding energy
• SHELL THE ELECTRON OCCUPIES (the FURTHER away from the nucleus the electron is, the LOWER the binding energy)

Question 11

Excitation

Answer 11

• when electrons move around within an atom
• to move an electron up a shell (further from the nucleus) energy must be ADDED
• when an electron moves down a shell energy must be REMOVED/LOST

Question 12

Characteristic interaction

Answer 12

• involves the FILAMENT electron and an ORBITAL electron of a target atom
• filament electron enters a target atom, strikes an orbital electron (inner shell)
• if the energy is greater than the binding energy of the orbital electron, it is removed from orbit

Question 13

Characteristic radiation

Answer 13

• losing an inner shell electron results in an unstable atom, so outer shell electrons will drop to fill the vacancies
• when this electron drops into an inner shell:
  
  • gives off potential energy (heat)
  • characteristic x-ray photon

Question 14

Characteristic x-ray

Answer 14

• kinetic energy of the projectile electron must be equal to or greater than the binding energy
• x-ray photon created has energy equal to the difference in the binding energies of the orbital electrons involved
  
  • k characteristic x-rays
    
    • specific energies

Question 15

Bremsstrahlung radiation

Answer 15

• NO ACTUAL INTERACTION with the electrons of the target atom
• projectile electron completely MISSES the orbital electrons as it passes through a target atom, but comes close enough to the nucleus to be influenced by its electric field
  
  • because the electron is negative and the nucleus is positive, there is a force of attraction
  • this causes the projectile electron to slow down and change direction: releasing energy (x-ray)

Question 16

Bremsstrahlung radiation cont

Answer 16

• the closer the projectile electron gets to the nucleus, the MORE it is influenced by the nucleus
• when it changes direction, the loss of kinetic energy is released as an x-ray
  
  • can lose any amount of energy (all,some)
  • slight direction change: LOWER ENERGY X-RAY
  • large direction change: HIGHER ENERGY X-RAY

Question 17

Interactions that produce heat

Answer 17

• excitation

- ionization (with outer shell electrons)

Question 18

Interactions that produce radiation

Answer 18

• characteristic

- bremsstrahlung