Exam 2 - Chapter 12

Question 1

Organic or Inorganic have covalent bonds?

Answer 1

organic

Question 2

Organic or Inorganic have low boiling points?

Answer 2

organic

Question 3

Organic or Inorganic burn in air?

Answer 3

organic

Question 4

Organic or Inorganic have high melting points?

Answer 4

inorganic

Question 5

Organic or Inorganic are water soluble?

Answer 5

inorganic

Question 6

Organic or Inorganic are soluble in nonpolar solvents?

Answer 6

organic

Question 7

Organic or Inorganic have ionic bonds?

Answer 7

inorganic

Question 8

Organic or Inorganic do not burn in air?

Answer 8

inorganic

Question 9

Alkanes are less dense than water, and mostly unreactive, except that they burn vigorously in air

Answer 9

TRUE

Question 10

Alkanes are found in natural gas, gasoline, and diesel fuels

Answer 10

True

Question 11

Alkanes are nonpolar and insoluble in water, and they have low boiling points

Answer 11

true

Question 12

in combustion, an alkane reacts with oxygen at high temperatures to produce carbon dioxide, water, and energy

Answer 12

true

Question 13

is the most common hexose. • is found in fruits, vegetables, corn syrup, and honey. • is also known as dextrose and blood sugar in the body. • is a building block of the disaccharides sucrose and
lactose and of polysaccharides such as cellulose and
glycogen.

Answer 13

D-Glucose

Question 14

an aldohexose with the formula C6H12O6,

• is obtained from the disaccharide lactose, found in milk.

• is important in the cellular membranes of the brain and
nervous system.

-cause of galactasemia

Answer 14

D-Galactose

Question 15

• is a ketohexose with the formula C6H12O6.

• is the sweetest of the carbohydrates, twice as sweet as
sucrose (table sugar).

• is obtained as one of the hydrolysis products of sucrose.

Answer 15

D-Fructose

Question 16

The most stable forms of pentose and hexose sugars are

Answer 16

Haworth: five- or six-atom rings.

Question 17

Haworth structures are produced from the reaction of a

carbonyl group and a hydroxyl group in the same molecule.

Answer 17

True

Question 18

Haworth Alpha

Answer 18

Alpha OH Hydroxyl is below

Question 19

• a disaccharide also known as malt sugar.
• composed of two D-glucose molecules.
• obtained from the hydrolysis of starch.
• used in cereals, candies, and brewing.
• found in both the α and β forms.

Answer 19

Maltose

Question 20

Maltose is linked by an _____ glycosidic bond formed from the α —OH on carbon 1 of the first glucose and the —OH on carbon 4 of the second glucose.

Answer 20

α-(1 —> 4)

Question 21

Lactose is a disaccharide of β-D-galactose and α- or β-D-glucose.

The bond in lactose is a _____glycosidic bond because the —OH group on carbon 1 of β-D-galactose forms a glycosidic bond with the —OH group on carbon 4 of a D-glucose molecule.

Answer 21

β-(1 —> 4)

Question 22

Sucrose, or table sugar,

• consists of α-D-glucose and β-D-fructose.

• has an _____ -glycosidic bond between carbon 1 of
glucose and carbon 2 of fructose.

Answer 22

α,β-(1—> 2)

Question 23

•cannot form an open chain or be oxidized.

• cannot react with Benedict’s reagent and
is not a reducing sugar. The sugar we use to sweeten our cereal, coffee, or tea is sucrose. Most of the sucrose for table sugar comes from sugar cane (20% by mass) or sugar beets (15% by mass).

Answer 23

Sucrose

Question 24

• a storage form of glucose in plants, found as insoluble
granules in rice, wheat, potatoes, beans, and cereals.

• composed of two kinds of polysaccharides: amylose and
amylopectin.

Answer 24

Starch is

Question 25

____ which makes up about 20% of starch, consists of 250 to 4000 α-D-glucose molecules connected by α-(1 4)-glycosidic bonds in a continuous chain. Polymer chains of amylose are coiled in a helical fashion.

Answer 25

Amylose

Question 26

• makes up as much as 80% of starch. • is a branched-chain polysaccharide. • contains glucose molecules connected by α-(1 4)- and α-(1 6)-glycosidic bonds.

Answer 26

Amylopectin

Question 27

contains glucose molecules connected by α-(1 4)- and | α-(1 6)-glycosidic bonds.

Answer 27

Amylopectin

Question 28

α-(1 4)-glycosidic bonds in a continuous chain

Answer 28

Amylose (and others)

Question 29

Starches hydrolyze easily in water and acid to give smaller saccharides, called ____, which then hydrolyze to maltose and finally glucose.

Answer 29

dextrins

Question 30

In our bodies, these complex carbohydrates

Answer 30

• are digested by the enzymes amylase in saliva and maltase in the intestines. • provide about 50% of our nutritional calories from the glucose obtained in digestion.

Question 31

____ is • a polymer of glucose that is stored in the liver and muscle of animals. • hydrolyzed in our cells at a rate that maintains the blood level of glucose and provides energy between meals. • similar to amylopectin but more highly branched. The glucose units in glycogen are joined by α-(1 4)- glycosidic bonds, with branches attached by α-(1 6)- glycosidic bonds that occur every 10–15 glucose units.

Answer 31

Glycogen

Question 32

• similar to amylopectin but more highly branched. The glucose units in glycogen are joined by α-(1 4)- glycosidic bonds, with branches attached by α-(1 6)- glycosidic bonds that occur every 10–15 glucose units.

Answer 32

Glycogen

Question 33

_____ the major structural unit of wood and plants, • is a polysaccharide of glucose units in unbranched chains with β-(1 4)-glycosidic bonds. • cannot form hydrogen bonds with water, making it insoluble in water. * gives a rigid structure to the cell walls in wood and fiber. * is more resistant to hydrolysis than are the starches. * cannot be digested by humans because humans cannot break down β-(1 4)-glycosidic bonds.

Answer 33

Cellulose

Question 34

• cannot be digested by humans because humans cannot break down β-(1 4)-glycosidic bonds.

Answer 34

Cellulose

Question 35

Draw Glyceraldehyde (aldotriose), Threose (aldotetrose), Ribose (aldopentose), and Fructose (ketohexose)

Answer 35

proud of you man

Question 36

Objects such as hands that have nonsuperimposable mirror images are ____

Answer 36

chiral

Question 37

Objects such as hands that have nonsuperimposable mirror images are ____

Answer 37

chiral

Question 38

When stereoisomers cannot be superimposed, they are | called ____

Answer 38

enantiomers

Question 39

Identify the types of glycosidic bonds in each of the following: A. Cellulose B. Amylose Amylopectin

Answer 39

A. Cellulose β-(1 4)-glycosidic bonds B. Amylose α-(1 4)-glycosidic bonds Amylopectin α-(1 4)- and α-(1 6)-glycosidic bonds

Question 40

_____ are a type of unbranched polysaccharide that consist of repeating disaccharide units. Each disaccharide unit is composed of one amino sugar molecule and either one uronic acid or one galactose molecule.

Answer 40

Glycosaminoglycans

Question 41

Glycosaminoglycans: Each disaccharide unit is composed of...

Answer 41

...one amino sugar molecule and either one uronic acid or one galactose molecule.