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