Chem exam 2

What is ammonium sulfate?

(NH₄)₂SO₄

What is ammonium nitrite?

NH₄NO₂

What is ammonium sulfide?

(NH₄)₂S

What is hydrosulfuric acid (formula + other name)?

H₂S; hydrogen sulfide

"hydro___ic acid" naming pattern

hydrogen + ___ide (e.g. hydrochloric = hydrogen + chloride)

Na⁺

K⁺

NO₃⁻

CH₃CO₂⁻

Cl⁻

Br⁻

F⁻ salts — exceptions (insoluble)?

Ca²⁺

SO₄²⁻ salts — exceptions (insoluble)?

Ca²⁺

OH⁻ and O²⁻ compounds — generally soluble or insoluble? exceptions (soluble)?

insoluble; Na⁺

S²⁻ salts — generally soluble or insoluble? exceptions (soluble)?

insoluble; Na⁺

CO₃²⁻ and PO₄³⁻ salts — generally soluble or insoluble? exceptions (soluble)?

insoluble; Na⁺

List the 6 steps for writing net ionic equations

1-write reactants 2-exchange cations for products 3-dissociate all soluble salts/strong acids/strong bases (not Ca(OH)₂) 4-balance 5-cross out spectator ions 6-rewrite NIE

In a NIE

what happens to solubles vs insolubles?

What is a spectator ion?

ion that appears unchanged on both sides; crossed out in NIE

Can you break up a polyatomic ion when dissociating?

no — e.g. SO₄²⁻ stays as SO₄²⁻

List all 9 strong acids

HCl

Which of the "hydro___ic" acids is weak?

H₂S (hydrosulfuric)

List the 4 strong bases

NaOH

Ca(OH)₂ — strong or weak base? trick?

strong

List the 9 oxidation number rules in order

1-elemental=0 2-monatomic ion=charge 3-Grp1A=+1 4-Grp2A=+2 5-F=−1 6-H=+1 7-O=−2 8-Grp7A=−1 9-Grp6A=−2

What is the sum rule for oxidation numbers?

sum of all ox# = overall charge of the substance

Oxidizing agent — what does it do

what happens to it?

Reducing agent — what does it do

what happens to it?

What do n

l

What are the allowed values of l for a given n?

0 to (n−1)

What are the allowed values of mₗ for a given l?

−l to +l (including 0)

What does each value of l correspond to (subshell letter)?

0=s

Order of orbital filling (aufbau)?

1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p

EM spectrum — order from longest to shortest wavelength

radio > microwave > infrared > visible > UV > X-ray > gamma

EM spectrum — order from lowest to highest frequency

radio < microwave < infrared < visible < UV < X-ray < gamma

EM spectrum — order from lowest to highest energy

same as frequency order (radio → gamma)

Visible light — order from longest to shortest wavelength (ROY G BIV)

red > orange > yellow > green > blue > indigo > violet

Visible light — which color has highest frequency/energy?

violet

Relationship between wavelength and frequency

c = λν; inversely proportional (c = 3×10⁸ m/s)

Formula for energy of a photon

E = hν = hc/λ

What is Planck's constant?

h = 6.626×10⁻³⁴ J·s

How to get frequency from wavelength?

ν = c/λ

How to get wavelength from energy?

λ = hc/E

How to get energy from frequency?

E = hν