Introduction to Organic Chemistry

Question 1

What does a molecular formula show?

Answer 1

The actual number of atoms in a molecule or element.

Question 2

What does an empirical formula show?

Answer 2

The simplest whole number ratio of atoms in a compound

Question 3

What does a structural formula show?

Answer 3

arrangement of atoms in a molecule without showing all the bonds

eg) ch3ch2ch2ch2oh

Question 4

What does a skeletal formula show?

Answer 4

show the bonds of carbon skeleton and functional groups not carbon and hydrogens

Question 5

What does a displayed formula show?

Answer 5

Shows the arrangement of atoms showing all the bonds and atoms in the molecule.

Question 6

Meaning of homologous series..

Answer 6

A group of compounds that have the same functional group and general formula.

Question 7

How to do nomenclature?

Answer 7

1) find longest carbon stem

2) functional group tells you the suffix

3) number the carbon chain so functional group sits on lowest possible number carbon as it has priority

Question 8

Where do curly arrows always begin from?

Answer 8

They begin from area with electrons. double bond/lone pair

Question 9

Structural isomers meaning

Answer 9

Structural isomers have the same molecular formula but different structural formula.

There are 3 types of structural isomers:

1. chain
2. positional
3. functional group

Question 10

Chain isomerism meaning

Answer 10

same molecular formula but different arrangement of carbon skeleton

Question 11

Positional isomerism meaning

Answer 11

same molecular formula but different position of the functional group on carbon skeleton

Question 12

Functional group isomerism meaning

Answer 12

same molecular formula but different functional group

Question 13

Stereoisomerism meaning

Answer 13

same structural formula but different arrangement of atoms in space.

Question 14

When only can E/Z isomerism occur?

Answer 14

When there is a double c=c bond as you can’t twist the double bond to fit another isomer.

Question 15

When is it E/Z isomerism?

Answer 15

When you have 2 different atoms/groups of atoms on the same carbon.

Question 16

How do you identify is something is E/Z?

Answer 16

Its z “ze zame zide’ if the groups are directly next to eachother

Its E “opposiet’ if the same groups are opposite each other

Question 17

How to identify E/Z isomerism when we have 4 different groups around the double bond.

Answer 17

Use CIP rules.

label the carbons as 1 & 2

Calculate atomic number of the first element directly bonded to c=c.
The atom with highest atomic is number is given a higher priority.

If needed to go down chain to figure out atomic number.

the 2 higher priorities depending on their position determines if an isomer is e or z