Main difference – Glucose vs Galactose

Carbohydrates are the major components of every living organisms. Glucose and also galactose room carbohydrates. Monosaccharides space the building blocks of bigger carbohydrate molecules. The main difference in between Glucose and also Galactose is the position of every hydroxyl team in the 4th carbon; the place of hydroxyl group (-OH) in the fourth carbon is horizontal in the chair confirmation of the Glucose whereas the place of hydroxyl group (-OH) in the 4th carbon is upward in the chair check of the Galactose.

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Key areas Covered

1. What is Glucose – Definition, molecule Formula, chemistry Structure, Properties 2. What is Galactose – Definition, molecule Formula, Properties 3. What space the Similarities in between Glucose and also Galactose – Outline of typical Features 4. What is the Difference in between Glucose and also Galactose – Comparison of vital Differences

Key Terms: Aldohexose, Carbohydrates, D-Glucose, Galactose, Glucose, Hexose, molecule Formula, Monosaccharides



What is Glucose

Glucose is a an easy sugar. It is a monosaccharide. The molecule formula of Glucose is C6H12O6. That chemical framework has 4 –OH groups along with a -CH2OH group. Since it has six –OH groups, glucose is dubbed a Hexose. In the Fischer projection, glucose has a terminal aldehyde group. Therefore, glucose is dubbed an aldohexose.


Figure 1: The chair confirmation of D-Glucose

The over image shows the basic structure of glucose. This picture indicates the glucose has four chiral centers. (A chiral center is a carbon atom having actually four different groups attached to it.) Therefore, glucose has actually stereoisomers. 

The naturally developing glucose is well-known as D-Glucose. The isomer that D-Glucose is L-Glucose. But the L-Glucose go not take place naturally. Glucose is water soluble and also is colorless when liquified in water. Glucose can happen as an open up chain or together a cyclic structure. Yet the open up chain is frequently unstable and spontaneously converts right into cyclic form. The melting point of glucose is about 1460C (for alpha-D-Glucose).

Aqueous solutions of glucose room able come rotate plane polarized light. D-Glucose rotates light clockwise and L-Glucose rotates light anticlockwise. Glucose act as a monomer for the development of a number of important polysaccharides. Some polymers that have glucose as the monomer encompass starch, cellulose, and glycogen.

What is Galactose

Galactose is a basic sugar and also a monosaccharide. The molecule formula the galactose is likewise C6H12O6. That chemical structure has four –OH groups in addition to a -CH2OH group. Same as glucose, galactose is also an aldohexose due to the visibility of six carbon atoms and also a terminal aldehyde group.


Figure 2: Fischer projection of D-Galactose

Galactose can exist one of two people in the open chain form or the cyclic form. Galactose contributes to the development of part disaccharides such together Lactose (Glucose + Galactose) and also Galactan (composed the Galactose). The melting allude of galactose is around 1670C. Galactose is additionally soluble in water, but the solubility is less than that of glucose.

Similarities between Glucose and also Galactose

Glucose and Galactose have six carbon atoms.The molecule formula is the same for both molecules.Both space Monosaccharides and simple sugars.Both room aldohexose molecules.

Difference between Glucose and Galactose


Glucose: Glucose is a an easy sugar composed of C, H, and also O atoms and tastes sweet.

Galactose: Galactose is a straightforward sugar composed of C, H, and O atoms and also is much less sweeter than glucose.

Position that –OH Group

The main difference between glucose and galactose is the chemistry structure; the position of each –OH group present in both molecules. This distinction occurs in the fourth carbon atom. The adhering to image mirrors this in detail.


Figure 3: Glucose vs. Galactose

Glucose: The –OH group of the fourth carbon (from the top) of D-Glucose is directed towards right side.

Galactose: The –OH group of the fourth carbon the D-Galactose is directed in the direction of the left side.


Glucose: Glucose is much more stable.

Galactose: Galactose is much less stable.


Glucose: Glucose is sweeter.

Galactose: Galactose is less sweeter 보다 Glucose.

Melting Point

Glucose: The melting allude of glucose is about 146-150oC.

Galactose: The melting point of galactose is around 167oC.


Glucose and also Galactose are an extremely important straightforward sugars together monosaccharides and also polysaccharides, i beg your pardon are developed after their polymerization. The chemical formula and the molar fixed of both molecules are the same, however the difference in between glucose and galactose lies in the plan of –OH teams along the carbon chain.

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1. Steane, Richard. “Molecular framework of glucose and also other carbohydrates.” structure of glucose and also other carbohydrate molecules. N.p., n.d. Web. Accessible here. 29 June 2017.  2. “Galactose.” Chemistry LibreTexts. Libretexts, 04 Mar. 2017. Web. Obtainable here. 29 June 2017.

Image Courtesy:

1.”Beta-D-Glucose” by Yikrazuul – Own occupational (Public Domain) via Commons Wikimedia 2. “Methyl-α-D-galactose” through Andromeas – Own occupational (CC0) via Commons Wikimedia 3. “GlucoseGalactose”By lord Biro – Glucosetatuetata.jpg (Public Domain) via Commons Wikimedia