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Chemistry A Level > Alkenes > Flashcards

Flashcards in Alkenes Deck (16):
1

What are stereoisomers?

Compounds with the same structural formula but a different arrangement in space

2

What is E/Z isomerism?

Stereoisomerism in terms of restricted rotation around a C=C double bond

3

What special part is needed in the name of an alkene?

En or Ene

4

What is the name of the main bond and the secondary bond in a double bond?

Main bond = Sigma bond
Secondary bond = Pi bond

5

How does a pi bond form?

The sideways overlap of two P orbitals

6

Which bond is weaker, sigma or pi?

Pi bond

7

What do the CIP rules state about E/Z isomerism?

The group with a larger atomic mass on the end of a bond is the higher priority group.

8

What do E and Z mean in E/Z isomerism?

E = Entgegen = Apart = Opposite sides
Z = Zusammen = Together = Same sides

9

What are the four addition reactions of alkenes and what are their conditions?

1. Addition of Hydrogen - Nickel catalyst
2. Halogens (i.e Cl2) - RTP
3. Hydrogen Halide (e.g. HBr)
4. Addition of Water - Phosphoric acid catalyst

10

What is the mechanism of addition to alkenes and how is it shown?

Electrophilic addition
1. Line from double bond to delta positive charge atom, and line from the molecule's bond to the delta negative atom
2. Line from the electron pair on the negative ion
3. Complete new product

11

What does electrophile mean?

Attracted to pairs of electrons

12

What does Markownikoff's rule state?

The non-hydrogen atom goes to the carbon with most carbons attached

13

How is atom economy calculated?

Mr of desired product
---------------------------------- x 100
Sum of Mr of all products

14

How is percentage yield calculated?

Actual amount
--------------------------- x 100
Theoretical amount

15

How does addition polymerisation work?

Multiple small monomers

16

How can we deal with polymer waste?

1. Producing photodegradable/ biodegradable polymers
2. Combustion of waste polyerms to generate energy
3. Reuse of material as a feedstock for the chemical industry