Section A Flashcards
What does saturated mean?
A saturated compound is a compound that contains only single carbon to carbon bonds
What does unsaturated mean?
An unsaturated compound is a compound containing at least one carbon to carbon double bond
What type of reactions do unsaturated compounds partake in?
Addition reactions
What is an addition reaction?
A reaction where two molecules combine to form a single molecule
How do you distinguish between a saturated hydrocarbon and unsaturated hydrocarbon?
Add bromine water and the unsaturated hydrocarbon will decolourise the bromine water quickly
What is an isomer?
Compounds with the same molecular formula but different structural formulae
How are chemical properties of isomers?
Isomers have different chemical properties
How are the physical properties of isomers?
Usually different
What are three factors that can affect the boiling point and volatility of hydrocarbons?
Hydrogen bonding
Polarity
London dispersion forces
Describe hydrogen bonding between molecules
Hydrogen bonding occurs when hydrogen is attached to a highly electronegative element and the large difference in electronegativity leads to large dipoles between molecules. Hydrogen bonding increases boiling point and volatility as stronger attractions between molecules means more energy is required to desperate the molecules
Describe polar bonding between molecules
Two atoms bonded together that have different electronegativities will have dipoles called a polar bond. It a compound with polar bonds is not symmetrical then the compound will be polar. Polar bonding increases boiling point and volatility as stronger attractions between molecules means more energy is required to depressed the molecules.
Describe London dispersion forces between molecules
A hydrocarbon that has more electrons will have a larger electron cloud which means that it’s electron cloud can have a larger distortion meaning that temporary dipoles will be larger. These will induce larger dipoles in a neighbouring molecule so there will be stronger attractions between the molecules. London dispersion forces increases boiling point and volatility as stronger attractions between molecules means more energy is required to separate the molecules.
Why are ionic and polar compounds soluble in polar solvents?
The attractions between the dipoles in the compound and the dipoles in the solvent enable the solvent molecules to surround the solute molecules and hence the solute dissolves.
Why are non-polar compounds insoluble sin polar solvents?
There are no attractions between the solute molecules and the solvent molecules
Why are hydrogen bonded compounds soluble in water?
Hydrogen bonds form between the compound and the water
