Chem 2 Exam 1 Dr. Kriley

Dr Kriley GCC Chemistry 2

3 main gases in the atmosphere

nitrogen, oxygen, carbon dioxide. N,O,CO2

3 types of nitrogen fixation

atmospheric, biological, industrial

example of atmospheric fixation & what chemical is related

lightning → 30 mil tons of HNO3 / yr

who is the father of chemical warfare?

borne haber

when was acid rain first created / named

1852

major air pollution events?

london smog (1952), india cyanide gas leak (1984), chernobyl radiation (1986), fukushima tsunami (2011)

examples of environmental damage as a result of air pollution

smog, acid rain, ozone depletion

carcinogens (4)

asbestos (insulation), benzene (gasoline), nirosamines (cured meat), saccharin (sweetner → NOT A CARCINOGEN)

common air pollutants (name 2)

sulfur oxide (sox), nitrogen oxide, hydrocarbons, carbon monoxide, photochemical oxidants (ozone o3)

chlorofluorocarbons definition

destroys ozone rich layer, allows UV radiation

montreal protocol

“end production of CFC’s by 1996”

Full combustion equation

fuel + o2 → co2 + h2o + E

partial combustion equation

fuel + o2 → co OR c +h2o + (less)E

primary energy sources (2)

petroleum and natural gas

solutions to pollution

solid particulates, remove gas (wet limestone), catalytic converters → unburned hydrocarbons

causes of air pollution

asbestos, beryllium, metal filings

what uses the most greenhouse gases?

electricity and heat and agriculture

what gases contribute to greenhouse gasses the most?

CO2!!!, CFC, Methane, N2O

why are phosphates bad?

increase eutrophication: lake→marsh→land

what is the coliform count

presence of E coli = coliform # increases = increased health hazard

what is the algal count

increased algae = excess nutrients and poor control

biochemical oxugen demand (BOD) ppm levels in pollution

1 = no organic pollution

20 = some org pollution

100-400 = high org pollution

key toxic pesticides

DDT (eagle killer), dieldrin, kepone

hazards of toxic pollutants in the water

kills wildlife, decrease reproduction, accumulates in animals (ie mercury in tuna)

2 natural sources of acid rain

lightning, volcanic eruptions

an unnatural source of acid rain

burning fossil fuels

america;s annual solid waste?

paper

kinetics

the study of speed or rates of chemical reactions by which they occur

thermodynamics

measured decrease in concentration of a reactant or an increase in concentration of a product in TIME

rate of appearance equation of AB with the example: A_2(g)+B_2(g) → 2 AB_(g)

AB = Δ[AB] / 2 (Δt)

rate of disappearance equation of A₂ with the example: A_2(g)+B_2(g) → 2 AB_(g)

A₂= -Δ[A₂] / 2 (Δt)

what 5 factors affect reaction rates?

1. nature of the reacting substance

2. physical state of subdivision of reactants (i.e. more surface area = more sites of rxn)

3. temperature

4. concentration

5. presence of a catalyst

how is a rate determined

by experimenting

rate equation

rate = k [A]^m[B]ⁿ[C]^p

(t/f) K’s value changes based on concentration of reactants/products

FALSE

(t/f) K’s value does not change over time

TRUE

FIRST ORDER rate equation

ln([A]t) / [A]₀ = -Kt OR ln([A]t) = -Kt + ln[A]₀

FIRST ORDER HALF TIME rate equation

[A]_t = ½ [A₀]

units for first order

s^-1

SECOND ORDER rate equation

1/[A]_t - 1/[A]₀ = Kt

SECOND ORDER HALF TIME rate equation

t ½ = 1 / (K[A]₀)

units for second order

M^-1 s^-1

ZERO ORDER rate equation

[A]_t = [A]₀ - Kt

ZERO ORDER HALF TIME rate equation

t ½ = ([A]₀) / 2K

while determining rxn rates with a mechanism, when should you stop?

AFTER IT SAYS SLOW

collision theory of rxn rates

for a rxn to occur, ions, atoms, or molecules must first collide

arrhenius rate equation

ln (k₂)/(k₁) = (Ea / R) (1/T₁ - 1/T₂)