Chem exam #3 connect homework part two
Rank the following synthetic polymers from the most to the least recycled PET, PVC, and HDPE
- PET - HDPE (milk jugs are made of HDPE and are frequently recycled) - PVC (both pvc and LDPE are most difficult to reuse and thus are the least recycled type of palstic)
Describe the properties of ethylene
- colorless gas - produced at oil refineries - flammable
What are potential drawbacks to the manufacture and use of polylactic acid?
- lactic acid comes from corn, so PLA manufacture competes with other corn uses - PLA softens at 60 degrees C, so its use is limited to low-temperature applications
What are some common household substances that are bases?
- oven cleaner - household ammonia
What are the advantages of recycling?
- the amount of waste in landfills is reduced - recycling may contribute to lower pollution of air, water, and soil during manufacture - recycling helps us to conserve natural resourced such as petroleum, timber, and water
Describe landfills
- they can leak unwanted materials into the surrounding area - landfill space is plentiful in som regions
Place the following types of plastics in order from most recycled ( at the top of the list) to least recycled
1) containers/packaging 2) durable goods 3) nondurable goods
List the types of municipal waster in order of abundance, starting with the greatest amount of waste at the top
1) paper 2) food scraps 3) yard trimmings 4) plastics 5) metals
Place the "four R's" for increasing sustainability in order of their desirability, starting with the most desirable activity
1) reduce 2) reuse 3) reuse 4) recover
Marine organisms such as mollusks, sea urchins, and coral have shells composed of __________ and these species are affected by the levels of _______ ions in seawater
CaCO3-; CO3 2-
- more ordered structure - opaque - stronger - higher melting point - greater rigidity These properties are describing what?
HDPE
- irregular tangle of polymer chains - transparent - less stregnth - lower melting point - stretchy These properties are describing what?
LDPE (food wrap and grocery bags)
What are the fates of plastics that are not recycled?
Landfill, incinerator, and placed in ocean
What type of synthetic polymer is the most recycled?
PET
____ is used in the manufacturing of carpeting
PP
_____ is used to fabricate food wrap
PS
How many different ways can the monomers for PVC, PP, and PS be orientated to form a polymer? Most common?
Three (head to tail
neutralization is the reaction between ______ and __________________
acid and hydroxide ion
SO2, NO2, and C)2 all produce ___________ solutions in water
acidic
Plastics are/arent' readily biodegradable
aren't
Normal seawater is slightly _________ with a pH of around _______
basic; 8.2
What is a common application for PET?
beverage bottles
An amino acid contains
carboxylic acid and amine
Both ozone and UV radiation have been used as alternative disinfectants to chlorine-containing compounds in the water treatment process. However, ________ must be added to the water after either of these treatment methods in order to protect the water after it leaves the treatment site
chlroine
Proteins are formed through
condensation polymerization
Polylactic acid (PLA) is a ________ polymer formed when units of lactic acid are joined together. For each covalent bond that forms in the chain a molecule of _________ is released
condensation; H2O
What are different forms of PS?
crystal and expandable
PET cab be separated from other polymers by
density
In polymer manufacturing, a blowing agent is a
gas or a substance capable of producing a gas that is used to manufacture foamed plastic (pentane in PS)
Polymers have ______ molecular masses
high
Lakes in limestone regions have a ________ acid-neutralizing capacity
higher
In what way does increasing ocean acidity affect cereal reefs?
increasing acidity leads to a decrease in the amount of CO3 2- ion available to build coral reefs
Why is NH3 able to act as a weak base?
it reacts with H2O to release small amounts of OH ions
The physical properties of a polymer can be drastically altered by changing the _______ of the polymer chain
length
When a mixture of polymers is melted together the resulting product is __________ valuable than a homogeneous recycled plastic. The properties of the mixed material are ___________, resulting in its use as parking lot bumpers or disposable plastic pots
less; inconsistent
Esters
link PET monomers together
Amides
link protein monomers together
Lakes in granite areas tend to have _______ pH values than lakes in limestone regions
lower
What reflects the relationship between molecular shape and the strength of dispersion force?
molecules with a large surface area have more points of contact and therefore experience stronger dispersion forces
What is the primary raw material used to synthesized poylmers?
petroleum
The term ________ is sometimes used as a synonym for synthetic poymer
plastic
An acid that dissociates completely in aqueous solution is called a
strong acid
Covalent bonds are ____________ than intermolecular forces
stronger
packing materials designed and used in such a way to reduce their environment impact are called _________ packaging materials
sustainable
Ocean acidification is correctly described as
the lowering of ocean pH due to increased atmospheric CO2
Polymers that can be reshaped when heated are called ________ polymers
thermoplastic
Polylactic acid (PLA) is a ________________ polymer that is most useful at ___________ temperatures
thermoplastic; lower
PET has
two different monomers