What Is Wood Composition Chemical Properties and Uses
Wood is a hard-fibrous material building the trunk and branches of trees or shrubs. The trees are first grounded, and the wood logs are then cut in the sawmills to smaller sizes, and these wooden pieces are then used for making furniture. The most famous and largely used wood type is softwood that is Plywood's.
The Density of Wood
Wood density affects how timber is classified and where it can be used. The relationship between timber hardness and density :
< 480 kg/m3 -Very soft
485–560.kg/m3 -Soft
565–800.kg/m3 -Firm
805–960.kg/m3 -Hard
> 965 kg/m3-Very hard
Characteristics of Wood
It is lightweight and strong
Wood maintains its thermal properties, therefore it is resistant to high temperatures
Heat conductivity of wood is comparatively low contrasted to aluminum, marble, steel, or glass
It can absorb noise and echo especially in Plywood's
It is not a good conductor of electricity.
Wood Advantages
To contribute to sustainable development the wood and its derivative products are the best suitable material because of the technician and environmental qualities.
Apart from is an eco-friendly material, wood brings other great features like high stability, strength, flexibility, versatility that make the wood products one of the biggest references of the habitats, decoration, construction, packaging. Wood is the only material that decreases the CO2 radiation, as plays an essential role to slow down Climatic Change.
Wood as a Material: Different Uses
The total number of wood-based items is enormous—some figures put it as high as 10,000. The versatility of wood, as well as its many desirable qualities, such as high strength for its weight, workability, and aesthetic appeal, allow such broad application. However, there are several drawbacks to using wood. It will, for example, fire and decay. It is hygroscopic (moisture-absorbing), and it changes dimensions as it absorbs or loses moisture. Furthermore, as a biological product, wood has a wide range of quality. Understanding the dynamic nature of this material is important for reducing the effects of these inherent undesirable properties, as well as making proper use of the many existing wood-growing plant species and producing the best possible wood quality in the forest. An analysis of the structure, chemical composition, and properties of wood may provide this insight.
Classification of Wood
Wood can be broadly categorized as Softwood and Hardwood. Density is a significant determinant of the durability of wood. Hardwoods, meaning denser than softwoods, are more effective and more long-lasting.
Softwood – It originates from the coniferous trees. These trees are also identified as evergreen trees as leaves do not drop till the new ones develop. Softwood normally grows in areas having a cold climate. Coniferous trees grow fast; therefore, they are less costly as compared to hardwood. They are more sustainable as they can be readily grown. Soft Wood has shades of yellow or red and is less costly compared to Hardwood.
Softwoods are Often Used for:
Panels
Plywood
Particleboards (compressed wood)
Dry-erase boards
Toys
Hardwood – It originates from deciduous trees that have broad leaves, provides fruits or nuts, and are usually inactive in the winter. Hardwoods have an extra dense structure about softwoods. Hardwood has darkened shades of red and brown and is a bit high-priced.
Hardwoods are Often Used for:
Flooring
Furniture
Utensils
Boats
Baseball bats
Instruments
Model aircraft (Balsa)
Types of Wood for Furniture Especially:
Softwood:
Plywood (highly popular in furniture making)
Pinewood
Cedarwood
Spruce wood
Deodar wood
Hardwood:
Teakwood
Rosewood
Oakwood
Maple wood- Rubberwood (Environment friendly)
Marandi wood
Why Buy Rubberwood and Its Uses?
Rubberwood is a light-colored, moderate tropical hardwood derived from the Pará rubber tree (Hevea brasiliensis), which is typically found in rubber plantations. Rubberwood is sometimes marketed as an "environmentally friendly" wood because it is made from plantation trees that have previously served a useful purpose. Rubberwood has a thick grain that is easily managed in the kiln drying process. This material is used for making furniture, toys, and kitchen accessories. It has a depth of approximately 9500 psi, stiffness of 1.3 million psi, and hardness of 500 pounds.
How Plywood is a Better Choice for Furniture?
Plywood is a smart option for most types of use that includes walls, subfloors, and furniture. The benefits of plywood hold its availability and price, as long as you aren't set on the more costly hardwood varieties. It is very hard and the thinner cuts are effortless to work with. Plywood that is covered with a good quality cover can be painted to look like any wood and is smooth to paint.
The Types of Plywood You can Choose:
Softwood plywood
Hardwood plywood
Tropical plywood
Aircraft plywood
Decorative plywood (overlaid types of plywood)
Flexible plywood
Marine plywood
FAQs on Wood in Chemistry Structure Composition and Properties
1. What is wood made of chemically?
Wood is primarily composed of the biopolymers cellulose, hemicellulose, and lignin.
- Cellulose: A polysaccharide with repeating units of (C6H10O5)n, forming the structural framework.
- Hemicellulose: A branched carbohydrate polymer that binds cellulose fibers.
- Lignin: A complex aromatic polymer that provides rigidity and resistance to decay.
- Minor components include resins, tannins, oils, and inorganic minerals (ash).
2. What is the chemical formula of cellulose in wood?
The chemical formula of cellulose is (C6H10O5)n, where n represents the number of repeating glucose units.
- Each repeating unit comes from β-D-glucose.
- Glucose monomers are linked by β-1,4-glycosidic bonds.
- Cellulose forms long, straight chains that hydrogen-bond together, giving wood its tensile strength.
3. Is wood an element, compound, or mixture?
Wood is a heterogeneous mixture of organic polymers and inorganic substances.
- It contains multiple compounds such as cellulose, lignin, and hemicellulose.
- These substances are physically and chemically combined in varying proportions.
- Because it does not have a fixed chemical formula, wood is not a pure compound.
4. What happens chemically when wood burns?
When wood burns, it undergoes combustion, reacting with oxygen to form carbon dioxide, water, and heat.
- Main reaction (for cellulose):
(C6H10O5) + 6O2(g) → 6CO2(g) + 5H2O(g) - This is an exothermic reaction that releases energy.
- Incomplete combustion may produce carbon monoxide (CO) and soot (C).
5. What is dry distillation of wood?
Dry distillation of wood is the thermal decomposition of wood in the absence of air.
- Occurs at high temperatures without oxygen.
- Produces charcoal (C), wood tar, methanol (CH3OH), and gases like CO and CO2.
- This process is also called pyrolysis.
6. Why is wood considered a renewable resource in chemistry?
Wood is considered a renewable resource because it is produced by photosynthesis and can be replenished naturally.
- Plants convert carbon dioxide and water into glucose:
6CO2(g) + 6H2O(l) → C6H12O6(aq) + 6O2(g) - Glucose polymerizes to form cellulose in wood.
- As long as forests are sustainably managed, wood can be regenerated.
7. What is the difference between hardwood and softwood chemically?
Chemically, hardwood and softwood differ mainly in their lignin structure and relative composition of polymers.
- Hardwood: Contains more complex lignin (with syringyl units).
- Softwood: Contains simpler lignin (mainly guaiacyl units).
- Both contain cellulose and hemicellulose but in different proportions.
8. How is paper chemically produced from wood?
Paper is produced by chemically separating cellulose fibers from lignin in wood pulp.
- In the Kraft process, wood is treated with sodium hydroxide (NaOH) and sodium sulfide (Na2S).
- Lignin dissolves, leaving mostly cellulose fibers.
- The fibers are washed, pressed, and dried to form paper sheets.
9. What is the pH of wood and is it acidic or basic?
Wood is generally slightly acidic, with a pH between 4 and 6.
- The acidity comes from organic acids such as acetic acid formed from hemicellulose.
- Acidity can affect metal corrosion and adhesive performance.
- pH varies depending on tree species and moisture content.
10. What gases are released when wood decomposes?
When wood decomposes thermally or biologically, it releases gases such as CO2, CO, and CH4.
- Thermal decomposition (pyrolysis) produces CO, CO2, CH4, and hydrogen (H2).
- Biological decay under anaerobic conditions produces methane (CH4).
- Aerobic decomposition mainly produces CO2 and water.
