Reactions of Alkanes Flashcards
Why are alkanes fairly unreactive?
It is because of the lack of polarity in the bonds and due to the strength of the bonds. The lack of polarity and the general symmetrical structure of alkanes (tetrahedral geometry) often result sin non-polar bods.
Alkanes ___ readily, undergo substitution with free ___ and elimination reactions under high temperatures or with a ____.
Burn
Radicals
Catalyst
What are 3 types of reactions?
- Substitution
- Elimination
- Addition
Define substitution.
Substitution is the process where one atom or molecular fragment is replaced by another atom or molecular fragment.
Define elimination.
A reaction where atoms or molecular fragments are removed from adjacent carbon atoms on molecule, forming a double bond. Atoms (fragments) are removed only, nothing is added.
Define Addition.
A reaction where the double bond opens and new molecular fragments (or atoms) are added to the double bond without anything being removed.
What is a combustion reaction?
A combustion reaction is a type of chemical reaction in which a compound and an oxidant are reacted to produce heat and a new product. The general form of a combustion reaction can be represented by the reaction between a hydrocarbon and oxygen, which yields carbon dioxide and water: hydrocarbon + O2 → CO2 + H2O.
What do alkanes undergo substitution with?
With halogens
What is necessary for the reaction to take place?
U.V. Light
Why is the attacking species in alkanes a free radical?
Due to the polarity and due to the strength of the bonds.
The reactions are __ reactions.
slow
One commercially important elimination reaction is known as ____.
Cracking
Explain the elimination process for alkanes.
The process can either be done using a catalyst or using heat. In this reaction large hydrocarbon molecules are broken into smaller and more useful molecules.
What do these elimination reactions produce at least one of?
An Alkene.
