chem103

Question 1

Given the three compounds: (i) Acetic acid (ethanoic acid), (ii) 2-hydroxyethanal (iii) methyl formate (methyl methanoate), which are constitutional (structural) isomers of one another?

Answer 1

They are all constitutional isomers of one another.

Question 2

Which of the compounds below is a secondary alcohol that is infinitely water-soluble (ketone)

Answer 2

2-propanol

Question 3

The compounds arranged so that their boiling points decrease from left to right (highest to lowest) are:

Answer 3

Pentanol, Propanol, Methyl ethyl ether, butane

Question 4

In the following pairs of compounds (dissolved in water) ______ is acidic and ______ is basic.

Answer 4

Formic acid (acidic), methylamine (basic)

Question 5

Esters are synthesized from two classes of organic compounds. These two types of compounds are:

Answer 5

Alcohols and carboxylic acids

Question 6

Oxidation of aldehyde

Answer 6

Carboxylic Acid

Question 7

If the “pendant” group attached to the main chain of the polymer is hexyl, the polymer must be poly-1-

Answer 7

Octene (6+2=8)

Question 8

A polyester can form from

Answer 8

A carboxylic acid and an alcohol

Question 9

When heated to its glass transition temperature, Tg, polyethylene

Answer 9

Becomes softer and more flexible

Question 10

The combination of 1,8-diaminoctane and suberic acid (diacid shown below) produces Nylon-

Answer 10

8,8

Question 11

The specific rotation of D-tartaric acid is -12.0. What will the specific rotation be for L-tartaric acid?

Answer 11

+12.0

Question 12

Of the following compounds, the one which exhibits optical isomerism is:

Answer 12

2-chloropropanoic acid

Question 13

Flash paper (nitrocellulose) is made by converting some of the _____ groups of the. B-D-glucose repeating unit in cellulose to ____ groups.

Answer 13

Hydroxy,nitro

Question 14

Fats belong to the class of compounds called ______, which are very soluble in _______

Answer 14

Lipids; nonpolar solvents

Question 15

To form its cyclic hemiacetal pyranose form, the hydroxyl H on carbon number _____ adds to the carbonyl oxygen.

Answer 15

5

Question 16

An unsaturated fatty acid is:

Answer 16

CH3(CH2)7CH–CH(CH2)7-COOH

Question 17

The primary structure of a protein refers to

Answer 17

Its sequence of amino acids

Question 18

The size chain of the amino acid, serine, is -CH2OH. Another name for serine is:

Answer 18

2-amino-3-hydroxypropanoic acid

Question 19

The secondary a-helical structure of proteins is held together by ______ bonds

Answer 19

Hydrogen

Question 20

The nitrogen base that is present in RNA but not in DNA is:

Answer 20

U (uracil)

Question 21

The addition of one mole of HBr to one mole of ethene produces:

Answer 21

Bromoethane

Question 22

The octane number of a compound is less than 100. The compound could be:

Answer 22

N-Octane

Question 23

Which set of properties listed best describe the compound chloroform (CHCl3)?

Answer 23

Nonflammable and toxic

Question 24

The lowest molar mass alkene is _____ and the lowest molar mass alkyne is

Answer 24

Ethylene, acetylene

Question 25

The compound 2,2,4,4-tetramethylhexane is a structural isomer of:

Answer 25

Decane (C10H22)

Question 26

For poly-1-hexene the "pendant" group is

Answer 26

Butyl

Question 27

Soap can be produced by reacting _______ with _________

Answer 27

Triacylglycerol (fat), NaOH (aq)

Question 28

Starch is a polymer of __________ and cellulose is a polymer of __________

Answer 28

A-D glucose, B-D glucose

Question 29

Of the following compounds the one which is optically active is:

Answer 29

2-chloropropanoic acid

Question 30

The reduction of ethanal with H2 produces

Answer 30

Ethanol

Question 31

Two components that could be combined to make n-propyl myristate, an ester ingredient in a perfume product are: (myristic acid has 14 C atoms.)

Answer 31

CH3CH2CH2OH and CH3(CH2)12COOH

Question 32

In the following pairs of compounds (dissolved in water), _______ is acidic and _______ is alkaline (basic).

Answer 32

Acetic acid, ethylamine

Question 33

Structure of DNA

Answer 33

Found in all biological molecules Unique arrangement in a single chain Secondary structure is depicted as single letters. Two complementary strands of DNA bind together through complementary base, pairing in an antiparallel fashion.

Question 34

DNA

Answer 34

Deoxyribose sugar Thymine base Double stranded

Question 35

RNA

Answer 35

Ribose sugar Uracil base Complex intrastrand structures Can form ribosomes through catalytic molecules Usually single strand

Question 36

Fatty acid components

Answer 36

Unbranched carboxylic acids Range from about 10 to 20 carbons Contain an even number of carbon atoms -COCH= only functional group. Some have carbon-carbon double bonds. Most fatty acids have carbon-carbon double bonds, the as-isomers predominate.

Question 37

Nucleic Acids

Answer 37

Have a nitrogenous base, five membered sugar, 1-3 phosphate groups. EX: Cytosine, ATP, cAMP, NAD+

Question 38

Lipids

Answer 38

Non-polar biological compounds (soluble in diethyl ether, dichloromethane and acetone). Heterogenous class of compounds (diverse structures)

Question 39

Steroids

Answer 39

Three cyclohexanes and one cyclopentane in a fused ring system.

Question 40

Triglycerides

Answer 40

Melting points of fatty acids increases as the number of carbons in the hydrocarbon chain increases. Insoluble in hard water.

Question 41

Oil (triglyceride)

Answer 41

Rich in unsaturated fatty acids; liquid at room temperatures

Question 42

Fats (triglyceride)

Answer 42

Rich in saturated fatty acids, semi-solid or solids at room temperature

Question 43

Saturated fats

Answer 43

Made up of carbon molecules that do not contain any double bonds between the carbon molecules

Question 44

Haworth projection

Answer 44

Simple sugars go through an intermolecular reaction to form pyranose or furanose rings. Strcutural stability is increased Naming convention changes

Question 45

Monosaccharides made from ketones form

Answer 45

Ketoses

Question 46

Simplest ketose

Answer 46

Dihydroxyacetone (not usually active)

Question 47

Xylose

Answer 47

Naturally in nuts, cannot be metabolized

Question 48

Lyxose

Answer 48

Bacteria, rare

Question 49

Alcohol

Answer 49

R-OH

Question 50

Ester

Answer 50

R-COO-R

Question 51

Amine

Answer 51

R-NH2

Question 52

Ketone

Answer 52

RCOR

Question 53

Aldehyde

Answer 53

R-CHO

Question 54

Amide

Answer 54

R-CONH2

Question 55

Carboxylic Acid

Answer 55

R-COOH

Question 56

Ether

Answer 56

R-O-R

Question 57

Carbohydrates

Answer 57

C6H12O6 Poly-hydroxy-ketone or poly-hydrox-aldehyde Di (2) saccharides Tri (3) saccharides Oligo (several) saccharides

Question 58

Polysaccharides

Answer 58

Large polymers of sugar

Question 59

Monosaccharides

Answer 59

One sugar containing an aldehyde (aldoses) or a ketone (ketoses) EX: glucose (a polyhydroxaldehyde), frutose (a polyhydroxyketone)

Question 60

Optical isomerism

Answer 60

When substances have the same molecular formula and structural formula. Same formula, different 3D arrangements.

Question 61

Analine

Answer 61

Attached to an aromatic ring

Question 62

Amine

Answer 62

Nitrogen atoms with a lone pair

Question 63

Properties of Alkynes

Answer 63

Non-polar and insoluble in water Only london-dispersion forces density is less than water benzene with 6 carbons = liquid @ room temperature

Question 64

Properties of Alkanes

Answer 64

Insoluble in water, low density Boiling points: Only london-dispersion forces. Relatively low. BP increases w/size Methane, propane, butane: gases Pentane (C5): liquid Paraffin wax (C20 or more) Solid Alkanes will float in water Colorless and odorless

Question 65

Phenols

Answer 65

Starting materials for the production of polymers.