Alkanes and Conformational Isomers of Alkanes

Question 1

What are alkanes? What is the formula?

Answer 1

Compounds with C-C and C-H single bond.
Cn H2n+2

Question 2

What is the formula for methane

Answer 2

C1H4

Question 3

What is the formula for ethane?

Answer 3

C2H6

Question 4

What is the formula for propane?

Answer 4

C3H8

Question 5

What is the formula for butane?

Answer 5

C4H10

Question 6

What is the relationship between an alkane’s size and its boiling point and melting point?

Answer 6

boiling point and melting point increase as size of alkane increases directly proportional to the increase in dispersion force

IN ISOMERS:
more branched means less surface area means less boiling point for isomers

Question 7

What is the parent chain name for C1H4

Answer 7

meth

Question 8

What is the parent chain name for C2H6

Answer 8

Eth

Question 9

What is the parent chain name for C3H8

Answer 9

Prop

Question 10

What is the parent chain name for C4H10

Answer 10

But

Question 11

What is the parent chain name for C5H12

Answer 11

Pent

Question 12

What is the parent chain name for C6H14

Answer 12

Hex

Question 13

What is the parent chain name for C7H16

Answer 13

Hept

Question 14

What is the parent chain name for C8H18

Answer 14

Oct

Question 15

What is the parent chain name for C9H20

Answer 15

Non

Question 16

What is the parent chain name for C10H22

Answer 16

Dec

Question 17

What is a straight chain alkane?

Answer 17

Carbon atoms connected to no more than 2 other carbons
- continuous chain

Ex: butane and pentane

Question 18

What is a branched like alkane?

Answer 18

carbon atoms connected to 3 or 4 carbon atoms
Ex: isobutane and isopentane

Question 19

What are alkyl group?

Answer 19

Partial structure that remains after the removal of one H from an alkane
- parts of a larger molecule

Question 20

What is the name replacement at the end of an alkyl group?

Answer 20

“ane” ending of alkane with “-yl” ending

Ex: methane (CH4) to methyl (CH3-)

Question 21

Why is rotation possible around C-C bond in alkanes?

Answer 21

Alkanes are cylindrically symmetrical

Question 22

What is a confirmation?

Answer 22

Different arrangements of atoms that results from bond rotation

Question 23

Which configuration is the most stable?

Answer 23

Staggered Confirmation

The confirmation that position all six C-H in an ethane as far away from one another as possible;
- lowest energy

Question 24

Which configuration is the least stable?

Answer 24

Eclipse Confirmation

The confirmation in which all six C-H bond in an enthane are as close as possible
- highest energy

Question 25

What is torsional strain?

Answer 25

Strain in a molecule caused by electron repulsion between eclipsed bond

Question 26

What is an anti confirmation?

Answer 26

Confirmation in which the two methyl group in a butane are as far apart as possible- 180 degree apart

Question 27

What is a gauche confirmation?

Answer 27

Confirmation in which the two methyl group are 60 degree apart

Question 28

What is a steric chain?

Answer 28

repulsive interaction caused by a gauche confirmation that occur when atoms are forced closer together than their atomic radii allow

Question 29

What is a partially eclipsed confirmation?

Answer 29

Confirmation of butane in which the two methyl groups are 120 degrees apart , but all bond overlap

Question 30

What is a fully eclipsed confirmation?

Answer 30

Confirmation of butane in which the two methyl groups are 0 degrees apart

Question 31

What is a primary carbon?

Answer 31

Carbon attached to only one carbon

Question 32

What is a secondary carbon?

Answer 32

Carbon attached to 2 carbon

Question 33

What is a tertiary carbon

Answer 33

Carbon that is attached to three carbon

Question 34

What is a quaternary carbon?

Answer 34

Carbon attached to 4 carbon

Question 35

What is a stereoisomer?

Answer 35

Compounds which have their atoms connected in the same order but differ in 3-D orientation

Question 36

What is a constitutional isomer?

Answer 36

Same molecular compounds with the same molecular formula