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Making soaps

Can someone clarify a few things:


Is a soap made in the following way:

Fat + Sodium hydroxide -> Glycerol + Sodium salt

So is the sodium salt that is formed the soap? Or do we have to do anything with it?

How do you make the fat?

Is the fat made by reacting glycerol + fatty acid? which gives triglyceride, is that a type of fat?

What I'm confused by is the book goes on about long chain carboxylic acids as fatty acids and then fats. Can someone help distinguish between the two.

Cheers
Original post by Super199
Can someone clarify a few things:


Is a soap made in the following way:

Fat + Sodium hydroxide -> Glycerol + Sodium salt

So is the sodium salt that is formed the soap? Or do we have to do anything with it?

How do you make the fat?

Is the fat made by reacting glycerol + fatty acid? which gives triglyceride, is that a type of fat?

What I'm confused by is the book goes on about long chain carboxylic acids as fatty acids and then fats. Can someone help distinguish between the two.

Cheers


Yes, the sodium salt is the soap.

A fat is made up of tri esterified glycerol (propan-1,2,3-triol) with long chain fatty acids. The most common animal fat is glyceryl tristearate. In this the glycerol has been esterified with three stearic acid molecules, C17H35COOH.

A fatty acid is simply a carboxylic acid with a long carbon chain. They are called fatty acids because they are made from fats.

The body manufactures fats naturally as a means of storing excess glycogen..
Reply 2
Original post by charco
Yes, the sodium salt is the soap.

A fat is made up of tri esterified glycerol (propan-1,2,3-triol) with long chain fatty acids. The most common animal fat is glyceryl tristearate. In this the glycerol has been esterified with three stearic acid molecules, C17H35COOH.

A fatty acid is simply a carboxylic acid with a long carbon chain. They are called fatty acids because they are made from fats.

The body manufactures fats naturally as a means of storing excess glycogen..

So are fats just long chained methyl esters? Formed from fatty acids and glycerol? Does it have to be glycerol
Original post by Super199
So are fats just long chained methyl esters? Formed from fatty acids and glycerol? Does it have to be glycerol


They have to be triesters based on glycerol.
Reply 4
Original post by Super199
So are fats just long chained methyl esters? Formed from fatty acids and glycerol? Does it have to be glycerol


Biodiesel is made of long chained methyl (and ethyl) esters.

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