Hydrocarbons Flashcards
What is the simplest family of hydrocarbons?
The simplest family of hydrocarbons is called the alkanes.
What is a homologous series?
A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula.
How are the bonds arranged.
The bonds around each carbon are arranged tetrahedrally.
Why do melting/boiling points increase as molecular size increases?
As molecular size increases, the strength of the intermolecular forces increases, therfore it takes more energy to break the bonds.
What is an isomer?
Molecules with the same molecular formula but different structural formula.
What is the alkane’s general formula?
Cn2n+2
What is the alkene’s and cycloalkane’s general formula?
Cn2n
What do hydrocarbons produce when burnt?
All hydrocarbons burn producing carbon dioxide and water. The smaller molecules are dangerously flammable.
How do hydrocarbons interact with water?
Hydrocarbons do not mix with water, but usually float on top.
What molecules are saturated or unsaturated?
Since alkanes have only single bonds in their structures they are said to be saturated. Alkenes with a carbon to carbon double bond are said to be unsaturated.
What happens when bromine is reacts with an alkene.
The bromine “adds on” across the double bond of the alkene.
How can Hexane be formed?
Hexane is formed when hydrogen reacts with hexene.
What can be used to test for unsaturation?
The addition of Bromine water can be used as a test for unsaturation. If the bromine water is decolourised then it is unsaturated and therefore an alkene.
What are the cycloalkanes?
The cycloalkanes are a homologous series, their carbon atoms are joined up in a ring. The simplest cycloalkane has 3 carbon atoms.
What is an addition reaction?
In addition reactions the chemical that reacts with the alkene adds itself on across the double bond .
What is an endothermic reaction?
A reaction that takes in heat energy.
