Unit 2 Section 5 Mechanisms and Spectra Flashcards
What is an a polymerisation reaction?
Joining together lots of simple molecules to form a giant molecule.
What is an addition reaction?
Joining 2 or more molecules together to form a larger molecule.
What is an elimination reaction?
When a small group of atoms breaks away from a larger molecule.
What is an substitution reaction?
When one species is replaced by another.
What is an hydrolysis reaction?
Splitting a molecule into two new molecules by adding H⁺ and OH⁻ derived from water.
What is an oxidation reaction?
Any reaction in which an atom loses electrons.
What is an reduction reaction?
Any reaction in which an atoms gains electrons.
What is a redox reaction?
Any reaction where electrons are transferred between two species.
What do nucleophiles usually reactive with?
They donate electron pairs. They react with positive ions or polar bonds.
What will free radicals react with?
Anything.
What are the 2 ways that a covalent bond can break?
Heterocyclic and homolytic fission
Explain heterolytic fission.
The bond breaks unevenly. Both electrons move to one atom. This will produce a cation (electrophile) and an anion(nucleophile). This is shown by drawing a full head arrow to one of the atoms from the bond.
Explain homolytic fission.
The bond breaks evenly so each atom gains one electron. This gives 2 neutral free radicals.
This is shown by drawing half head arrows from the bond to each of the atoms.
What is the basic of infra-red spectroscopy?
A range of infra red radiation is shown through an organic compound. Some of these will be absorbed.
What is percentage transmittance?
How much of a frequency can get through an organic compound.
0% would mean all of it was absorbed.
What happens to the bonds in a molecule when they go through infra-red spectroscopy?
They will absorb different wavelengths meaning they can vibrate to a higher level.
The energy involved depends on the bond length and the size of the atoms.
What is the finger print region?
The area of a infra-red spectroscopy graph which is on the right. There are many different peaks and troughs and it is unique to each molecule.
