Final answer:
Soap is an alkaline compound made by combining the fatty acids in oils with sodium or potassium salts, through a process called saponification, which involves bases like NaOH or KOH.
Step-by-step explanation:
The alkaline compound made by combining the fatty acids in oils with sodium or potassium salts is known as soap. Soaps are formed when fatty acids, which are long-chain carboxylic acids found in animal fats and oils, are treated with a base such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). This process, termed saponification, yields glycerol and the sodium or potassium salts of fatty acids, like sodium palmitate or sodium stearate, depending on the specific fatty acids present in the fat or oil being used.
The reaction involved in soap-making goes to completion, where fats and oils are hydrolyzed under high pressure and temperature, in the presence of a strong base like sodium hydroxide. The fatty acids react with the base to form soap molecules, which have unique cleaning properties due to their amphiphilic nature, having both a hydrophobic hydrocarbon chain and a hydrophilic carboxylate group.