7.2 Bohr’s Theory Of The Atom

Question 1

Bohr’s revisions to atomic theory: electrons in specific orbits

Answer 1

-electrons are located in defined shells, which are located certain distances from the nucleus
-electrons cannot exist between defined shells
-electrons can gain energy to move up to a higher shell, or they can lose energy to move down to a lower shell
- electrons are more stable (have less energy) when they are closer to nucleus

Question 2

Bohrs contribution

Answer 2

Amount of energy electron has is related to how far it is from nucleus; atoms only emit or absorb light energy when their electrons jump between shells.

Question 3

of shells for an element

Answer 3

Related to row of periodic table it is found in:
First shell-2 electrons
Second shell-8 electrons
Third shell-8 electrons
Fourth shell-18
Fifth shell-18
Sixth- 32

Question 4

Standard atomic notation

Answer 4

Atomic number-protons
Mass number-total # of protons and neutrons in nucleus

Question 5

Standard notation for ions

Answer 5

-Ion: charged atom
-Negative ion: more electrons then protons
-positive ion: fewer electrons then protons
-ion charge: charge on an ion whether positive or negative

*when atom becomes charged, #of protons in atom doesn’t change, ion charge is only due to change in # of electrons.