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 compounds with nonmetals?

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 difference between absorption and emission?

Answer 10

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 11

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

Answer 11

• principle quantum number
• describes SIZE of the orbital

Question 12

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

Answer 12

• angular momentum number
• describes SHAPE of the orbital

Question 13

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

Answer 13

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

Question 14

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

Answer 14

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

Question 15

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

Answer 15

• sphere, sun
• possible for ALL values of n

Question 16

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

Answer 16

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

Question 17

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

Answer 17

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

Question 18

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

Answer 18

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

Question 19

how do you know the number of angular nodes?

Answer 19

same as l value of the orbital

Question 20

what is the aufbau principle?

Answer 20

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

Question 21

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

Answer 21

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 22

what is the pauli exclusion principle?

Answer 22

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

Question 23

what is hund’s rule? (bus seat rule)

Answer 23

electrons pair up only if they have to

Question 24

how do you calculate energy when given wavelength?

Answer 24

E = ((hc)/wavelength)

Question 25

what is the oxidation number of H in compounds with metals (or Boron)?

Answer 25

-1

Question 26

if given frequency, how do you find the energy of a photon?

Answer 26

frequency x planck’s constant = energy of a photon