Sugar Formula – Structure, Properties, Uses, Sample Questions

Sugar is a synthesized form of Sucrose and consists of elements Carbon, Hydrogen, and Oxygen. Carbon is a nonmetal present in group 14 of the periodic table. Carbon is represented by the symbol C, and its atomic number is 6. Hydrogen is the lightest element and colorless, tasteless, odorless, and flammable gas. Its atomic number is 1 and is represented with the symbol H. Oxygen is a nonmetal that is highly reactive in nature. It is present in group 16 of the periodic table. Its atomic number is 8 and is represented by the letter O.

Sugar

Sugar is a monoclinic crystal structure, soluble in water, and has a sweet taste. It is also called Sucrose with the molecular formula C₁₂H₂₂O₁₁. The sugar molecule is composed of two monosaccharides- Glucose and Fructose connected via a glycosidic bond. The linking of two monosaccharides is called a glycosidic linkage. In 1857, William Miller coined the word Sucrose. For human consumption, Sucrose must be refined. It is mainly used as a food ingredient because of its sweet taste. Sucrose is obtained from sugar canes or sugar beets.

Structure of Sugar

As discussed above, Sugar is made up of two monosaccharides connected via a glycosidic bond. The structure of sugar is illustrated below-

Sugar Structure

Physical Properties of Sugar

• Sugar appears in white crystalline solid form.
• The molecular weight of Sugar is 342.30 g/mol.
• Its Melting point decomposes at 459 K.
• The density of sugar is 1.587 g/cm³.
• It is soluble in water, and its solubility at a temperature of 20° C is 203.9g/100mL.
• Its standard enthalpy of combustion is 5647 kJ.mol^-1.

Chemical Properties of Sugar

• Sucrose/sugar can be dehydrated in the presence of Sulfuric acid to obtain a black solid that is rich in carbon and small quantities of SO₃. The chemical reaction is given below,

C₁₂H₂₂O₁₁ + H₂SO₄ → 11H₂O + 12C (black carbon-rich solid) + heat

• Sugar molecule (C₁₂H₂₂O₁₁) reacts with Chloric acid (HClO₃) to yield Hydrochloric acid, Carbon dioxide, and water.

C₁₂H₂₂O₁₁ + 8HClO₃ → 8HCl + 11H₂O + 12CO₂

• Sucrose reacts with powerful oxidizing agents like Potassium nitrate (KNO₃) to produce a special type of fuel called rocket candy. The chemical reaction is given below-

C₁₂H₂₂O₁₁ + 6KNO₃ → 3K₂CO₃ + 3N₂ + 9CO + 11H₂O

Uses of Sugar/Sucrose

• Sucrose is used as a food preservative.
• Sugar is one of the important components of soft drinks.
• It also serves as an antioxidant.
• It acts as a food thickening agent and as a food stabilizer.
• Jams, Jellies, and sweets are prepared with the help of Sugar.
• Sucrose is used in baking for a rich brown color appearance.
• It is used as a chemical intermediate for detergents.

Frequently asked questions 

Question 1: Is Sugar/Sucrose soluble in ethanol?

Answer:

Sugar is slightly soluble in ethanol. Sugar which doesn’t dissolve settles at the bottom. If the alcohol is cold then it will dissolve even less of the sucrose.

Question 2: Sucrose is made up of what compounds?

Answer:

Sugar molecule is composed of two monosaccharides- Glucose and Fructose connected via a glycosidic bond. The linking of two monosaccharides is called as glycosidic linkage.

Question 3: Find the molecular weight of Sugar.

Answer:

Molecular formula of sugar is C₁₂H₂₂O₁₁.

Atomic weight of each Carbon atom = 12.011 

Atomic weight of each Hydrogen atom = 1.00784  

Atomic weight of each Oxygen atom = 15.999

Molar mass = (12 × 12.011) + (22 × 1.00784 ) + (11 × 15.999)

=342.30

Question 4: What is the function of sugar in the agriculture field?

Answer:

Sucrose is the common type of carbohydrate used for the carriage of carbon in plants. It is soluble in water and then transported into the phloem by plant cells, the special vascular tissue intended for sugar transport.

Question 5: How rich solid black carbon is prepared from sucrose?

Answer:

A rich solid black carbon is prepared by dehydrating the Sucrose in presence of Sulfuric acid. The chemical reaction is given below-

C₁₂H₂₂O₁₁ + H₂SO₄ → 11H₂O + 12C (black carbon rich solid) + heat

Question 6: Where Sucrose can be found?

Answer:

Sucrose found naturally in sugar cane, sugar beets, fruits- bananas, grapes, Vegetables – carrots etc. The Sucrose is processed into the compound sugar which is used in foods in our daily life.