What do we mean by the following in organic chemistry?

In organic chemistry, I came along the following notes:

Homologous series of alkanes
Alkanes are saturated organic compounds
Homologous series of alkenes
Alkenes are unsaturated organic compounds

Can you just describe the bold-italic words?

Thanks.

Homologous series - A series of organic compounds with the same functionaly group, but with each successive member differing by CH2.

Saturated - Single bonds in the hydrocarbon chain only.

Unsaturated - A hydrocarbon containing at least one C=C double bond.

Alkanes are saturated as they have single C-C and C-H bonds only.

Alkenes are unsaturated as they have at least one C=C double bond in the chain.

Hope this helps

Organic chemistry? Isn't that biology.

Organic chemistry? Isn't that biology.

1) Homologous series - they are analogous to functional groups, ie what characterises a particular organic compound family

2) saturated - single bonds between C-C

3) unsaturated - opposite of saturated, more than a single bond between C-C, ie double in alkenes, triple in alkynes

NB, you mention C-C because all C-H has to be single bonds due to H only having one electron to share in covalent bond

Homologous series - A series of organic compounds with the same functionaly group, but with each successive member differing by CH2.

Saturated - Single bonds in the hydrocarbon chain only.

Unsaturated - A hydrocarbon containing at least one C=C double bond.

Alkanes are saturated as they have single C-C and C-H bonds only.

Alkenes are unsaturated as they have at least one C=C double bond in the chain.

Hope this helps

Thanks for your reply.

What do you mean by ...successive member differing by CH2.

And, can you just explain "saturation" in a bit more detail?

By that I mean that the chain is increased by one carbon atom attached to two hydrogen atoms each time. E.g. butane differs from propane by CH2, and hexene differs from pentene by CH2.

Saturation is defined as: soaked, impregnated, or imbued thoroughly; charged thoroughly or completely; brought to a state of saturation.

So if you think about it, if each carbon atom has four bonds to other atoms, it has reached the maximum number of atoms it can have attached to it (as carbon has four electrons on its outer shell). This means it is saturated.

However, if there is a double bond then it may only be attached to three atoms therefore it is not fully saturated as more atoms can still be added to the atom before it reaches its maximum.

Thanks again so much.

Just a small thing. Can you just give me an example of how alkanes are saturated and alkenes are unsaturated? Just to understand it better.

Thanks again so much.

Just a small thing. Can you just give me an example of how alkanes are saturated and alkenes are unsaturated? Just to understand it better.

saturated - single C-C bonds, difficult to functionalise, ie can't do electrophilic addition of HBr

unsaturated - multiple bonds between C-C, easy functionalisation, ie can do electrophilic addition, that is can still add across the multiple bonds till the C-C gets saturated

hope that example clarifies the idea

Is tere a simpler example that shows how is this shown in the alkanes and alkenes organic compounds (i.e; methane, methene)?

Is tere a simpler example that shows how is this shown in the alkanes and alkenes organic compounds (i.e; methane, methene)?

you cannot get "methene", as that would violate that C-H must be single bonds.
simplest alkene is ethene, 2 carbons where you can have double bonds between C-C

are you sure you understand bonding?

Yes, I understand bonding, but seems I mentioned "methene" without paying attention to the existence of at least two carbons where the double bonds will be between.

Organic chemistry =/= biology

No, this is organic chemistry.