Alkanes and alkenes

How does increasing the carbon chain length of alkanes change their boiling point?

As the carbon chain length increases, so does the boiling point of the alkane.

This is because, as the carbon chain length increases, the surface area of the alkane increases.

This means more surface contact is possible between molecules.

This means the strength of the London forces between molecules is greater, so the boiling point increases.

How does increasing the branching of alkanes change their boiling point?

As branching increases, the boiling point of the alkane decreases.

This is because, as the branching increases, the surface contact between molecules decreases, giving fewer London forces between molecules.

This means the strength of the London forces between molecules is less, so the boiling point of the alkane decreases.

What are the products of complete combustion of an alkane?

CO2 and H2O.

What are the products of incomplete combustion of an alkane?

C or CO and H2O.

How do alkanes react with Halogens?

Through radical substitution.

Are alkanes saturated or unsaturated?

Saturated.

Are alkenes saturated or unsaturated?

Unsaturated.

Describe a C=C bond.

Sigma bond between the two carbon atoms formed from the head on overlap of two orbitals

A pi bond is formed from the sideways overlap of two p orbitals above and below the plane of the sigma bond.

What is the name of the reaction alkenes take to form saturated compounds?

Electrophilic addition.

What is a primary carbocation?

A carbocation with the positive carbon atom bonded to one alkyl group.

What is a secondary carbocation?

A carbocation with the positive carbon atom bonded to two alkyl groups.

What is a tertiary carbocation?

A carbocation with the positive carbon atom bonded to three alkyl groups.

How does the stability of carbocations change from primary to tertiary.

The stability of carbocations increases from primary to tertiary.

What is the major product of electrophilic addition of an alkene?

The product that forms the most stable carbocation intermediate.

What is the minor product of electrophilic addition of an alkene?

The product the forms the least stable carbocation intermediate.