exam #3

Question 1

what is an oxidation-reduction reaction?

Answer 1

electron transfer from one species to another

Question 2

what is the oxidation number of a free element?

Answer 2

0

Question 3

what is the oxidation number of a monatomic ion (ion of only one atom)?

Answer 3

the charge of the ion (like Cl- or Be2+)

Question 4

what is the oxidation number of H in most compounds?

Answer 4

+1

Question 5

what is the oxidation number of F in all compounds?

Answer 5

-1

Question 6

what is the oxidation number of O in most compounds?

Answer 6

-2

Question 7

what is the oxidation number for alkali metals? alkaline earth metals?

Answer 7

alkali metals = +1
alkaline earth metals = +2

Question 8

what is the oxidizing agent?

Answer 8

the reactant that undergoes “GER” and gains electrons

Question 9

what is the reducing agent?

Answer 9

the reactant that undergoes “LEO” and loses electrons

Question 10

what is the equation to find the energy of a single proton when given frequency?

Answer 10

(frequency)(planck’s constant) = energy in joules (J)

Question 11

what is the difference between absorption and emission?

Answer 11

absorption = gaining energy & jumping to a higher energy level (like 2 to 4)
emission = losing energy & falling from an excited state to a lower level (like 4 to 2)

Question 12

what is the quantum number “n” and what does it say about an orbital?

Answer 12

• principle quantum number
• describes SIZE of the orbital

Question 13

what is the quantum number “l” and what does it say about an orbital?

Answer 13

• angular momentum number
• describes SHAPE of the orbital

Question 14

what is the quantum number “ml” and what does it say about an orbital?

Answer 14

• magnetic quantum number
• describes ORIENTATION of the orbital in space

Question 15

what is the quantum number “ms” and what does it say about an orbital?

Answer 15

• spin magnetic quantum number
• describes ELECTRON SPIN of the orbital

Question 16

what do s orbitals look like and for what values of n are they possible?

Answer 16

• sphere, sun
• possible for ALL values of n

Question 17

what do p orbitals look like and for what values of n are they possible

Answer 17

• peanut, pair of pears
• possible for n=2 and higher

Question 18

what do d orbitals look like and for what values of n are they possible

Answer 18

• dutterfly, dragonfly
• possible for n=3 and higher

Question 19

what do f orbitals look like and for what values of n are they possible?

Answer 19

• full flower, fish frenzy
• possible for n=4 and higher

Question 20

how do you know the number of angular nodes?

Answer 20

same as l value of the orbital

Question 21

what is the aufbau principle?

Answer 21

when electrons are filling an orbital, they fill the lowest energy orbitals first (1s, 2s, etc.)

Question 22

what is the trick to remembering the ordering of orbitals from lowest to greatest?

Answer 22

1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
6s 6p 6d
7s 7p
(diagonal lines from right to left to tell ordering)

Question 23

what is the pauli exclusion principle?

Answer 23

each orbital can only contain up to two electrons, and if paired up, the electrons must be of opposite spins

Question 24

what is hund’s rule?

Answer 24

electrons pair up only if they have to