organic chem

Question 1

What is a homologous series?

What are examples homologous series?

Answer 1

A homologous series is a family of organic compounds with the same functional group and similar chemical properties.

Examples of homologous series are alkanes, alkenes, alcohols and carboxylic acids. 👍✌🏻

Question 2

What are the general characteristics of a homologous series?

Answer 2

• have a common functional group, thus exhibiting similar chemical properties
• have similar chemical properties
• gradual change in their physical properties(m.p, b.p, density) as we go down the series from one member to the next
• can be prepared by similar methods such as reaction of alkene with steam to form alcohol

Question 3

What is a functional group?

Answer 3

A functional group is a group of atoms or bonds common to a family of organic compounds, and which determines the principal chemical properties or reactions of the series.

Question 4

Suffixes and their homologous series (4)

Answer 4

• ane = alkane
• ene = alkene
• ol = alcohol
• oic acid = carboxylic acid

Question 5

Name two sources of energy.

Answer 5

Natural gas (mainly methane) and petroleum.

Question 6

What is petroleum?

What is the physical properties of petroleum?

Answer 6

Petroleum is a naturally occurring mixture of hydrocarbons (mainly alkenes)

Physical properties of petroleum:

• dark brown
• foul-smelling liquid
• does not flow easily

*must go through fractional distillation to the use of petrol be separated into useful fractions

Question 7

Useful fractions of petroleum:
What is the use of this fraction?
(a) petrol (gasoline)

Answer 7

Fuel for cars

Question 8

Useful fractions of petroleum:
What is the use of this fraction?
(b) naphtha

Answer 8

feedstock and main source of hydrocarbons used for production of a wide range of organic compounds in the petrochemical industry

Question 9

Useful fractions of petroleum:
What is the use of this fraction?
(c) paraffin (kerosene)

Answer 9

fuel for heating and cooking and for aircraft engines

Question 10

Useful fractions of petroleum:
What is the use of this fraction?
(d) diesel

Answer 10

fuel for diesel engines

Question 11

Useful fractions of petroleum:
What is the use of this fraction?
(e) lubricating oils

Answer 11

used as lubricants and as a source of polishes and waxes

Question 12

Useful fractions of petroleum:
What is the use of this fraction?
(f) bitumen

Answer 12

bitumen for making road surfaces

Question 13

Alkane
Explain what is an alkane and its characteristics.
Functional Group (FG) of Alkane
What is the general formula (GF) for alkane?

Answer 13

Alkanes are saturated hydrocarbons, in which all carbon-carbon atoms are single bonds. 
Functional Group: NONE
They contain only C-C and C-H bond.
GF: C(n)H(2n+2)
Characteristics:
Alkanes are generally unreactive.

Question 14

Alkene

Functional Group?

Answer 14

Alkene:
Functional Group
C=C (carbon-carbon double bond)

Question 15

Alcohols

Functional Group?

Answer 15

-O-H

Question 16

Carboxylic Acids

Functional Group?

Answer 16

-C
=O on top of C,
-OH continue horizontally from -C