Question

How do disaccharides dissolve in water?

Answer 1

Hint: Disaccharide, also known as double sugar, is any substance composed of two simple sugar molecules (monosaccharides) which are linked to each other. Disaccharides are water-soluble compounds and are crystalline.

Complete answer:
When two monosaccharides are joined by glycosidic linkage, a disaccharide is the sugar formed. One of each sugar molecule comes together in OH groups to release water molecules and form an oxygen bridge between them. This method is known as condensation.
Disaccharides, like monosaccharides, are simple water soluble sugars. Sucrose, lactose, and maltose are three common examples. All disaccharides are water soluble.
By forming hydrogen bonds with them, water dissolves disaccharides.
"Like dissolves like" is the simple rule.
In other words, in a polar solvent like water, molecules which are polar will dissolve.
A sucrose-disaccharide has many polar OH groups. Owing to the presence of a large number of polar OH groups, when dissolved in water, these OH groups form hydrogen bonds with water molecules.
Hydrogen bonds strongly attract water molecules to one another.
But disaccharides are also highly attracted to them, too. Water forms hydrogen bonds with molecules of sucrose. The water molecules will easily get sucrose between them, so sucrose dissolves in water.

Note:
Monosaccharides and disaccharides are soluble in water from three kinds of carbohydrates because they contain several free-OH groups that are polar and strongly attracted to water molecules, whereas polysaccharides have a complex structure. The polymer bond between polysaccharide sugar molecules prevents them from interacting with water molecules so that they are not soluble or less soluble in water.