GSCI 163. Lecture 12. Organic chemistry. What distinguishes organic chemistry from other areas of chemistry? Origins – compounds from plants and animals Organic compounds were though to have a “v ital force” and as such to be impossible to synthesize in laboratory.
What distinguishes organic chemistry from other areas of chemistry?
Origins – compounds from plants and animals
Organic compounds were though to have a “vital force” and as such to be impossible to synthesize in laboratory.
Friedrich Wöhlerdebunked this notion by synthesizing urea a common carbon based compound found in human urine.
The area of chemistry that studies carbon based compounds, hydrocarbons and respective derivatives.
In organic compounds, the bonds are covalent since the elements are non-metals. The most common elements in organic compounds are:
Hydrocarbons are a combination of carbon and hydrogen atoms. All other organic compounds are considered derivative of hydrocarbons.
How can we combine carbon and hydrogen atoms to make organic compounds?
The most important aromatic compound is the benzene ring. Benzene is a clear, colorless liquid with a distinct odor. It is carcinogenic.
Other common aromatic hydrocarbons are:
If an organic compound does not have an benzene ring, it is know as an aliphatic hydrocarbon.
They can be divided into four groups depending on the types of bonds:
Saturated = CnH2n+2
Alkanes are highly combustible reacting with O2 forming carbon dioxide, water vapor and releasing heat. If combustion is not complete, carbon monoxide and black sooty carbon is produced.
What is the octane rate?
100 = Trymethylpentane
Rings of saturated hydrocarbons
Properties similar to the alkanes, but have higher boiling points, melting point and densities than alkanes
These hydrocarbons have double bonds between two carbon atoms.
Most common: ethylene
Alkenes are very reactive and known as unsaturated hydrocarbons which react with H2 to form a corresponding alkane.
Hydrocarbons that have a triple bond between two carbon atoms.
Most common: acetylene
Used for welding application because of the high temperature of its flame: over 3000 C