organic chemistry.....aim 1

what are organic compounds?

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aim 2.....

 

HW From textbook “CHEMISTRY a Contemporary Approach”

 

Organic compounds contain carbon atoms which bond to one another in chains, rings, and networks to form a variety of structures.

 

           

Carbon with 4 valence e- is able to form four covalent bonds with other carbon atoms and other kinds of atoms. The four single bonds of the carbon atom are at the corners of a tetrahedron.

          

 

In a multiple covalent bond, more than one pair of electrons is shared between two atoms.

Example

 

 

H

 

H

 

 

 

H

 

 

 

 

 

H

 

 

 

 

 

 

 

 

 

 

|

 

|

 

 

 

 

\

 

 

 

⁄

 

 

 

 

 

 

 

 

 

H

—

C

—

C

—

H

 

 

 

C

=

C

 

 

 

H

—

C

≡

C

—

H

 

 

|

 

|

 

 

 

 

⁄

 

 

 

\

 

 

 

 

 

 

 

 

 

 

 

H

 

H

 

 

 

H

 

 

 

 

 

H

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ethane

 

ethene

 

ethyne

single bond

sharing of 1 pair of  e-

 

double bond

sharing of 2 pair of e-

 

triple bond

sharing of 3 pair of e-

 

Hydrocarbons are compounds that contain only carbon and hydrogen.

Example

CH4 and C3H6

 

Saturated hydrocarbons contain only single carbon-carbon bonds.

Example

 

 

H

 

H

 

 

 

 

 

 

 

H

 

H

 

H

 

H

 

H

 

 

 

 

|

 

|

 

 

 

 

 

 

 

|

 

|

 

|

 

|

 

|

 

 

H

—

C

—

C

—

H

 

 

 

H

—

C

—

C

—

C

—

C

—

C

—

H

 

 

|

 

|

 

 

 

 

 

 

 

|

 

|

 

|

 

|

 

|

 

 

 

 

H

 

H

 

 

 

 

 

 

 

H

 

H

 

H

 

H

 

H

 

 

ethane

 

 

 

pentane

 

Unsaturated organic compounds contain at least one double or triple bond.

Example

 

 

 

 

 

 

 

 

 

 

 

 

H

 

 

 

 

 

H

 

H

 

 

 

 

 

 

 

 

 

 

 

 

 

 

|

 

 

 

 

 

|

 

|

 

 

H

—

C

≡

C

—

H

 

 

 

H

—

C

—

C

=

C

—

C

—

C

—

H

 

 

 

 

 

 

 

 

 

 

 

 

|

 

|

 

|

 

|

 

|

 

 

 

 

 

 

 

 

 

 

 

 

 

 

H

 

H

 

H

 

H

 

H

 

 

ethyne

 

 

 

2-pentene

 

Isomers of organic compounds have the same molecular formula but different structures and properties.

Example

 

 

H

 

H

 

H

 

 

 

 

 

 

 

 

 

 

 

H

 

O

 

H

 

 

 

 

|

 

|

 

|

 

 

 

 

 

 

 

 

 

 

 

|

 

||

 

|

 

 

H

—

C

—

C

—

C

=

O

 

 

 

 

 

 

 

H

—

C

—

C

—

C

—

H

 

 

|

 

|

 

 

 

 

 

 

 

 

 

 

 

 

 

|

 

 

 

|

 

 

 

 

H

 

H

 

 

 

 

 

 

 

 

 

 

 

 

 

H

 

 

 

H

 

 

 

 

propanal

 

<-- name -->

 

propanone

 

 

 

 

 

C3H6O

 

 

<-- molecular formula -->

 

 

C3H6O

 

 

 

 

 

CH3CH2CHO

<-- condensed structural formula -->

CH3COCH3

 

 

 

TEST YOUR UNDERSTANDING

8/07

24 Which two compounds are isomers of each other?

(1) CH3CH2COOH and CH3COOCH2CH3         (2) CH3CH2CHO and CH3COCH3

(3) CH3CHBrCH3 and CH2BrCHBrCH3             (4) CH3CHOHCH3 and CH3CHOHCH2OH

25 Which formula represents an unsaturated hydrocarbon?

 

41 Given the formula of a substance:

What is the total number of shared electrons in a molecule of this substance?    (1) 22      (2) 11     (3) 9       (4) 6

1/06

45 Which formula represents an unsaturated hydrocarbon?

6/06

17 Which formula represents a hydrocarbon?

22 The compounds CH3OCH3 and CH3CH2OH are isomers of each other. These two compounds must have the same

    (1) density   (2) reactivity  (3) melting point  (4) molecular formula

1/04

19 All organic compounds must contain the element (1) phosphorus (2) oxygen (3) carbon (4) nitrogen

6/04

22 Which element must be present in an organic compound? (1) hydrogen (2) oxygen (3) carbon (4) nitrogen

6/05

21 Which element has atoms that can bond with each other to form long chains or rings?  (1) carbon (2) nitrogen (3) oxygen (4) fluorine

1/03

1. In saturated hydrocarbons, carbon atoms are bonded to each other by

(1) single covalent bonds, only                                         (2) double covalent bonds, only

(3) alternating single and double covalent bonds           (4) alternating double and triple covalent bonds

2.  How is the bonding between carbon atoms different in unsaturated hydrocarbons and saturated hydrocarbons?

8/03

23 Which structural formula correctly represents a hydrocarbon molecule?

25 Which structural formula represents a molecule that is not an isomer of pentane?

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