Chapter 4

Question 1

Properties of alkanes

Answer 1

• not reactive
• high temp cracking
• can undergo combustion

Question 2

What are Alkanes

Answer 2

Hydrocarbons with only single bonds to H and C, using SP3 carbons

Question 3

Relation between Alkyl and Alkanes

Answer 3

Alkyls are Alkanes minus 1 hydrogen

Question 4

Physical properties of Alkanes

Answer 4

• Hydrophobic
• Less dense than H2O (0.7)
• BP (MP) increases as MW increases

Question 5

utility of Alkanes

Answer 5

Used as Fuels and solvents

Question 6

reactions of hydrocarbons

Answer 6

• Combustion
• Cracking (large MW hydrocarbons —> smaller MW)
• Halogen (CH4 + Cl2 + Light)

Question 7

Shape of Hydrocarbons

Answer 7

• Linear = SP hybridized
• Planar = SP2 Hybridized
• Tetrahedral = SP3 hybridized

Question 8

What shape are 3 ring and 4 ring molecules?

Answer 8

planar

Question 9

Shape of cyclopropane

Answer 9

triangle

Question 10

Shape of cyclobutene

Answer 10

Square

Question 11

shape of cyclopentane

Answer 11

pentagon

Question 12

shape of cyclohexane

Answer 12

Hexagon

Question 13

Properties of cyclohexenes

Answer 13

• nonpolar
• BP (MP) increases as MW increases

Question 14

How are carbons numbered

Answer 14

start top right, go clockwise

Question 15

staggered newman projections

Answer 15

low E, can see molecules in the back

Question 16

Eclipsed Newman Projections

Answer 16

High energy, molecules in the back are stacked

Question 17

What gives the base name of Alkanes

Answer 17

The main (longest) chain of continuous carbon atoms

Question 18

when numbering the main chain where do you start?

Answer 18

start from carbon nearest to the first substituent

Question 19

What is the substituent group called?

Answer 19

Alkyl group

Question 20

How to organize substituents

Answer 20

• 2 or more different alkyls are listed in alphabetical order
• 2 or more of the same alkyl use prefixes (di, tri, etc)