Chemical and physical properties of sucrose sugar

Chemical Compound: Sucrose

Sugar (Sucrose) -- C12H22O11

The compound chosen for discussion in the paper is- sucrose. The reason behind choosing this compound is that it is a substance of everyday use, consumed worldwide. Its commonness has led people to consider sucrose as an ingredient whose solitary purpose is what it is commonly used for- as sugar- and not in the form of a chemical compound. Therefore, sucrose is chosen for study out of curiosity regarding it.

This paper will look into a chemical and physical description of sucrose, its economic significance, its relation to prior class studies, as well as its change of state. Employing various concepts like 'international system of measurements (SI)' units, the properties of the compound will be elucidated.

Compound Description

Physical description

Pure sucrose, often, takes the form of an odorless, colorless, fine crystalline powder having a sweet, pleasant taste. It can be prepared in solid form, as a liquid, or as a dry powder. Large crystals precipitated from sucrose's water solutions onto any nucleation surface or string form a popular confection, rock candy. At 186 degrees Celsius, sucrose melts, decomposing to become caramel; when combusted, sucrose decomposes into carbon dioxide, water and carbon. Through the process of hydrolysis, sucrose is broken down by water; however, this reaction is so very slow that one could watch a sucrose solution for several years and not notice any significant change. However, on adding enzyme (sucrase) the process of hydrolysis takes place at a rapid pace (edinformatics, n.d.).

Molecular description

Provide molecular weight, constituent elements, types of bonding, and polarity.

Molecular Weight

342.29648 g/mol (gram/mole)

Molecular Formula

C12H22O11

constituent elements

Carbon, hydrogen, Oxygen

XLogP3

-3.7

Hydrogen Bond Donor Count

8

Hydrogen Bond Acceptor Count

11

Rotatable Bond Count

5

Exact Mass

342.116212g/mol

Mono-isotopic Mass

342.116212 g/mol

Topological Polar Surface Area

190 A^2

Heavy Atom Count

23

Sucrose's glycosidic bond is sometimes called 'a-b-1-2 bond', owing to the fact that an alpha-OH molecule from glucose bonds with a beta-OH molecule of sucrose; also, we are going from glucose's #1 carbon atom to fructose's #2 carbon atom.

Properties description

Molecular Weight: 342.3

Melting Point: 320 to 367 " F (decomposes)

Boiling Point: Decomposes

Vapor Pressure: 0 mmHg (approximately)

Vapor Density (Relative to Air): data unavailable

Water Solubility: greater than or equal to 100 mg/mL at 66° F

Specific Gravity: 1.59 at 68.0 " F

Lower Explosive Limit (LEL): 0.045 gram/Liter (Cameo Chemicals, n.d.).

(F= Fahrenheit; mm= millimeter; Hg= mercury; mg= milligram; mL= milliliter)

Usage

Pharmaceuticals

Sucrose is an important constituent of cough syrups, due to its bodying property and solubility. Sugar (sucrose) also plays the role of a diluent, for controlling active ingredients' concentration in tablets; additionally, sugar acts as binder for holding together tablet ingredients.

Wound-healing

Scientists have proclaimed that sugar can successfully be utilized for treating serious burns and wounds, which don't respond to conventional treatment. Sugar, through dissolving in an open wound's tissues, creates an environment that checks the growth of bacteria. Sugar is also thought to supply the necessary nourishment, required for regrowth of damaged tissues.

Sugar-Based Products

Researchers are closely studying functionality of sucrose to develop useful products in many areas of application. Sucrose epoxies, sucrose esters and bio-plastics are some of the specific products, derived from sucrose, that have garnered industry representatives' and researchers' attention.

Exothermic

Several chemical processes are accompanied by release of energy, whether as light, heat or sound. Such reactions are called exothermic reactions. They may take place spontaneously, resulting in higher system entropy or randomness (?S > 0). These reactions are represented by negative flow of heat (i.e. The reaction system loses heat to surroundings) and decreased enthalpy (?H < 0). Exothermic reactions in laboratories generate heat or might even cause an explosion (Helmenstine, n.d.). This reaction depicts a nearly-one-minute time delay before proceeding. As the process of dehydration commences, the acid begins turning yellow. Since this reaction is of an exothermic nature, the dehydration rate accelerates with heating up of the acid. As sugar molecules get divested of water, heat produced in the reaction system converts water to steam; this subsequently expands the residual carbon to a smoking, porous, black column, which expands from the vessel, giving rise to an acrid, choking vapor that smells of burnt carbon.

Heat of reaction

Dehydration is the loss of water content (along with carbon and heat in sucrose following the chemical reaction of sucrose with sulfuric acid (H2SO4 ):

C12H22O11(s) ? 12C(s) + 11H2O (g) ?H = -918.9 kJ / mol

As the reaction shows, it generates heat and is hence depicted by a negative change in enthaloy of the system. This is an exothermic reaction..

This dehydrated sucrose releases water which dilutes the sulfuric acid. The subsequent reaction is also exothermic, releasing heat into the environment:

H2SO4(l) ? H2SO4(aq) ?H = - kJ / mol

The combined heat released due to the dual exothermic reactions accelerates the process of dilution and dehydration.

All products, reactants, and catalysts

Sugar is dehydrated:

C12H22O11 = 12C (graphite) + 11H2O (l)

Sulfuric acid is hydrated:

H2SO4. n H2O + m H2O = H2SO4 . n1 H2O + heat (2)

(n = .11 moles, m = 11 X 2.0 moles of sucrose = 2.2 moles, and n1 = 2.3 moles.) (Shakhashiri, 1983).

Special considerations

Sulfuric acid is a highly corrosive and strong acid that may damage one's skin. Therefore, safety goggles and gloves must be worn while handling it. Hot steam is produced in the course of the reaction. Thus, one must stand at a distance from the reaction vessel, and reduce the degree of contact of one's skin with the vapors from protection from burns. The remaining material should be placed back in the hood. The fumes can be irritating (Shakhashiri, 1983).

Summary of other possible reactions

None

Class Connection

Difference in state

Difference in the reactivity of the compound with the reactivity of a similar compound

Sucrose acts as a reducing agent. Its reactions with chlorates, perchlorates, and other oxidizing agents are explosive in nature. Sucrose can be hydrolyzed by action of yeast enzyme, invertase and the action of dilute acids (NTP, 1992). When concentrated form of sulfuric acid is added to it, sucrose chars quickly and exothermically. Sodium chloride is a generally unreactive compound. If a concentrated form of sulfuric acid or any other non-volatile acid is added to it, sodium chloride releases hydrogen chloridegas (Cameo Chemicals, n.d.).

Change in the heat of reaction

Given that the reaction's nature is exothermic; when the reaction is at its equilibrium and the system's temperature is increased, this rise in temperature will correspond to heating the reaction vessel. This heat influx will take the reaction away from its equilibrium state- equilibrium is restored by nature by removal of some of the extra heat. Since it is an exothermic reaction, it generates heat while proceeding further. According to Le Chatelier's Principle, the system reacts for removing additional heat; therefore, it must move reverse, thereby converting the products formed back into reactants. Conversely, when the system's temperature is decreased (i.e. If heat from the reaction system is removed), the reaction takes place in the direction that opposes this heat removal. Thus, forward reaction takes place for releasing heat, to counterbalance the heat which was lost by the reaction system. Here, one must remember that the reaction vessel is being maintained at some set temperature, thus, the net process (which may release or produce heat) doesn't actually alter the system's temperature. The extra heat generated is replaced or removed as is necessary for maintaining equilibrium and temperature (Blauch, 2001).

Difference in the molecular weight of this compound compared to similar compound

The molecular weight of sucrose is 342.29648 gram/mole (g/mol.), while that of similar salt, sodium chloride (NaCl) is 58.44g/mol. When temperature and pressure are same, then of these two compounds, that compound which has smaller particles will usually be more soluble. Larger the compound's molecules are, larger will be its size and molecular weight. Solvent molecules find it difficult to surround larger molecules. Excluding all the factors mentioned above, one can generally state that bigger particles have lesser solubility. Thus, the solubility of sodium chloride is more than sucrose.

Conclusion

Sucrose, also known as 'saccharose' is commonly called table sugar. Its molecular formula is C12H22O11. The systematic name of sucrose is I±-D-glucopyranosyl-(1

ss-D-fructofuranose. Sucrose is known best for its function in providing nutrition to humans; plants form sucrose, while higher animals do not. Though sugar is mainly consumed all over the world for obtaining sweetness in food, medicine, etc., it has many diverse roles to play in the area of food technology. Of these, the most vital are that sugar added in foods functions as preservative, sweetener, coloring agent, flavoring agent, bulking agent, texture modifier, and fermentation substrate. The various techniques of using sugar depend upon its relevant chemical and physical significance (Koivistoinen & Hyvonen, 1985).

Sucrose, a disaccharide of non-reducing nature, is constituted of fructose and glucose, linked through their anomeric carbon atoms. Commercially, sucrose can be obtained from sugarcane, beta vulgaris (commonly called sugar beet), as well as other plants. It is extensively utilized as an ingredient in foods, and as a sweetener. Sucrose on hydrolysis generates the 2 monosaccharides- fructose (ketohexose) and glucose (aldohexose), while on dehydration it generates a complex carbon-containing solid residue. On combustion, it yields carbon dioxide, water and carbon, while an action of sulfuric acid on sucrose leads to the latter's dehydration, and formation of elemental carbon (edinformatics, n.d.).