Chapter 11: Introduction to organic chemistry

Question 1

What is the Molecular Formula

Answer 1

• Formula that gives the actual number of atoms of each element in a molecule

Butane = C₄H₁₀

Question 2

What is the Empirical Formula

Answer 2

• Formula that gives the simplest ratio of atoms of each element in a compound
• Butane = C₂H₅

Question 3

What is the general formula

Answer 3

• This shows the number of atoms of each element in a substance that has n carbons
• All the molecules in a homologous series have the same general formula
• Alkenes C_nH_2n

Question 4

What is the Structual Formula

Answer 4

• This shows how the atoms are joined together in a molecule
• Butane - C₄H₁₀ -CH₃CH₂CH₂CH₃

Question 5

What is the Displayed Formula

Answer 5

• This shows all the bonds and atoms in a molecule
• In general the carbons are joined together to form a backbone

Question 6

What is the Skeletal Formula

Answer 6

• This uses lines to represent bonds
  
  • A single bond is -
  • A double bond is =
• Each point represents a C atom
• Other atoms are shown

Question 7

What are Alkanes

Answer 7

• Saturated hydrocarbons
• General formula C_nH_2n+2
• Unreactive
• React with oxygen exothermically so used as fuels

Question 8

How do you name a straight chain alkane

Answer 8

• Count carbons in main chain
• Add correct prefix meth = 1, eth = 2, prop = 3, but = 4
• Add ‘ane’ to the end

Question 9

What are structual isomers

What are the 3 types of structural isomerism

Answer 9

• Molecules with the same molecular formula but different structures
  
  • Chain isomers - different carbon chain
  • Position isomers- functional group in a different position
  • Functional Group isomers - has a different functional group

Question 10

What is a functional group

Answer 10

• The atom or group of atoms that is responsible for most of the chemical reactions of a molecule

c=c - alkenes

oh - alcohols

Question 11

What are halogenoalkanes

Answer 11

• Are compounds in which 1 or more hydrogens are replaced by halogen atoms

Question 12

What are Alkenes

Answer 12

• Hydrocarbons
• Contain a carbon carbon double bond
• Reactive
• Often used to make polymers
  
  • General formula C_nH_2n

Question 13

How do you name halogenoalkanes

Answer 13

• F - Fluoro Alkane
• Br - Bromo alkane
• Cl - Chloro alkane
• I - Iodo alkane

Question 14

What are the prefixes for 1, 2, 3, 4, 5, 6

Answer 14

• 1 = meth
• 2 = eth
• 3 = prop
• 4 = but
• 5 = pent
• 6 = hex

Question 15

What is Stereoisomerism

Name Geometric Isomers

Answer 15

• Molecules with the same molecular and structural formulae but have different spatial arrangement of atoms
• Molecules that have different arrangement of groups around the C=C

Question 16

E-Z Isomers arise when

Answer 16

• There is restricted rotation around the C=C double bond
• There are 2 different groups/atoms attactched to each of the carbons of the double bond

Question 17

How do you calculate which side has the highest priority on stereoisomers

Answer 17

1. Compare the atomic number of the atoms directly attached to each side of the double bond. Highest 1 = priority
2. If they are the same. Look at the 1 at distance 2 count up the atomic masses of each atom -highest = priority

Question 18

How to calculate the empirical formula

Answer 18

• Write out the mass/percentage of each element
• Divide each mass or percentage by the Ar
• Whichever is the smallest divide all numbers by this to find the simplest whole number ratio
• If the values are near 1/2 times them by 2 etc