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The Interstate Highway SystemIn 1919, a convoy of army trucks was sent on a journey across the United States, from Washington to San Francisco, to test the efficiency of the roadway system in case of an emergency. It took 62 days for the convoy to cross the nation, underlining the needs for better road infrastructures. The origins of the Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate System, can be traced back to 1941 when President Franklin D. Roosevelt appointed a National Interregional Highway Committee to evaluate the need and potential for a national highway system. A system of 33,900 miles of rural routes, plus an additional 5,000 miles of auxiliary urban routes was recommended. Funding for the system was first authorized in 1952, but the construction of such a massive public and freely accessible infrastructure was beyond the means of the state and federal governments. The first highway segments were thus toll roads. It was under President Eisenhower that the question of how to fund the Interstate System was resolved with the enactment of the Federal-Aid Highway Act of 1956, which in addition provided design standards for the system. Construction then proceeded rapidly and by 1991 the system was considered officially completed. As of 2010, the Interstate system totaled more than 47,100 miles.

https://people.hofstra.edu/geotrans/eng/ch3en/conc3en/map_interstatesystem.html

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IMF > KE IMF KE IMF < KE

Increasing EN

Special cases: (1) EN(O) > EN(Cl)

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Special cases: (1) EN(O) > EN(Cl)Special cases: (1) EN(O) > EN(Cl)(2) EN(H) EN(C)

A. ion-ion

B. dipole-dipole

C. London dispersion

Identify the most important intermolecular force for:

ClI BrBr

__________________

Predict which of these molecules has the highest BP?

__________________

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Are SiF4 and SF4 polar or nonpolar?

SiF4 SF4

A. polar polar

B. nonpolar polar

C. polar nonpolar

D. nonpolar nonpolar

Are AsF5 and BrF5 polar or nonpolar?

AsF5 BrF5

A. polar polar

B. nonpolar polar

C. polar nonpolar

D. nonpolar nonpolar

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Which molecule is expected to have the highest boiling point?

A. AsF5 52.8 C

B. BrF5 40.25 C

Are SO2 and SO3 polar or nonpolar?

SO2 SO3

A. polar polar

B. nonpolar polar

C. polar nonpolar

D. nonpolar nonpolar

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The partial negative charge on SO2 is...

A. on the sulfur atom’s side.

B. on the oxygen atoms’ side.

http://chemwiki.ucdavis.edu/Wikitexts/UCD_Chem_2A/ChemWiki_Module_Topics/Chemical_Bonding/Electrostatic_Potential_maps

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What IMF is responsible for SO3 having a higher BP than SO2?

A. ion-ionB. dipole-dipoleC. London

dispersion

BP (C)SO2 10SO3 45

Which molecule is expected to have the highest boiling point?

A. SF4 38 C

B. SF6 64 C

C. ??????

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What IMF is responsible for SF4 having a higher BP than SF6?

A. ion-ionB. dipole-dipoleC. London dispersion

The straight-chain isomer allows closer contact between the C4H10 molecules.

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10

0.87 atm

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