Glucose

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Glucose
Glucose powder sample.jpg
Store-grade glucose.
Names
IUPAC name
D-Glucose
Systematic IUPAC name
(2R,3S,4R,5R)-2,3,4,5,6-Pentahydroxyhexanal
Other names
Blood sugar
Corn sugar
Dextrose
D-Glucose
Grape sugar
Identifiers
Jmol-3D images Image
Properties
C6H12O6
Molar mass 180.16 g/mol
Appearance White crystalline solid
Odor Odorless
Density 1.54 g/cm3
Melting point α-D-glucose: 146 °C (295 °F; 419 K)
β-D-glucose: 150 °C (302 °F; 423 K)
Boiling point Decomposes
90.9 g/100 ml (at 25 °C)
Solubility Slightly soluble in alcohols
Insoluble in esters, ethers, hydrocarbons, halocarbons
Vapor pressure ~0 mmHg
Thermochemistry
209.2 J·K−1 ·mol−1
1271 kJ/mol
Hazards
Safety data sheet AcrosOrganics
Related compounds
Related compounds
Fructose
Tagatose
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Glucose (occasionally referred to as grape sugar) is an organic compound with the molecular formula C6H12O6, found in sugar. Glucose is classified as a sugar, a monosaccharide, more specifically a hexose (6 carbon atoms).

Glucose has 16 stereoisomers, with the D-isomer or D-glucose, also known as dextrose, being the most important. It is one of the few isomers that occur widely in nature.

Properties

Chemical

Glucose is the ubiquitous fuel in practically all biological organisms.

Physical

Glucose is an odorless, colorless white solid, with a sweet taste, very soluble in water, acetic acid, but less so in ethanol and methanol, and insoluble in most non-polar solvents, like hydrocarbons.

Availability

Glucose bars can be purchased from most stores. Purification may be required to remove additives or other contaminants.

Powdered glucose can be purchased from pharmacy and some food stores.

Glucose is made during photosynthesis from water and carbon dioxide, using energy from sunlight.

Preparation

Glucose is produced commercially via the enzymatic hydrolysis of starch, with corn starch being the most common form of starch used, though other sources of starch can be used.

Inversion of sucrose (table sugar) will yield glucose and fructose. This can be achieved by heating a mixture of water:sucrose in a ratio of 1:2, with 0.1% citric acid added as a catalyst (though other acids can be used, such as ascorbic acid or potassium bitartrate). The solution is heated up to 114 °C for a few hours for complete separation of the two monosaccharides.

However, glucose is best bought than made, as it is cheaply available

Projects

Handling

Safety

Store-grade glucose is safe to consume, however lab-grade glucose is generally not.

Storage

Glucose should be kept in closed bottles, away from moisture and animals.

Disposal

No special disposal is required. Discard it as you wish.

References

Relevant Sciencemadness threads