CARBONOIDS: ELEMENTS, CHARACTERISTICS AND USES - CHEMISTRY - 2025

The carbonids are all those elements that make up the so-called carbon family, group 14 (IVA) of the periodic table. The group is made up of a nonmetal element, carbon; two metalloid elements, silicon and germanium; and three metallic elements: tin, lead and flevorium.

These elements have four electrons in their outermost electronic shell, with the ns ² np ² configuration. They tend to use the +4 oxidation state; With the exception of lead, which, due to the effect of the pair of inert electrons, uses the oxidation state +2.

Charcoal, the representative element of the group of carbonids. Source: Pxhere.

The elements belonging to this family are chemically stable, not very reactive. But they are capable of forming hydrides and halides. Furthermore, the elements tend to form covalent bonds; although tin and lead (both metals) tend to form metallic bonds.

The values ​​of melting points, boiling points, and ionization energy tend to decrease as the atomic number of the elements in the group increases. Likewise, efficient concatenations decrease, leading carbon and its multiple CC bonds.

Elements and characteristics

Carbon

Non-metallic element with atomic number 6 and atomic weight 12.011 g / mol. Carbon is such an important element that organic chemistry is called the chemistry of carbon, since all its compounds are formed by this element.

Carbon is present in carbohydrates, lipids, proteins, and nucleic acids; that is, in all the molecules and macromolecules responsible for life. However, it is the seventeenth element in abundance in the earth's crust.

Carbon is the only element of the family that is found in the earth's crust in pure form. In addition, it combines with other elements to form petroleum and carbonates in rocks such as calcite (CaCO ₃), magnesite (MgCO ₃) and dolomite (MgCO ₃ · CaCO ₃).

Carbon has 5 allotropic forms: graphite, which appears as stacked sheets. The diamond is a crystal of cubic structure, tetrahedral in shape with carbon atoms located at its vertices.

Amorphous carbon is black powder in the form of soot. In fullerene, the carbon rings form molecular arrangements similar to soccer balls. And in graphene, we find a layer of carbon atoms arranged in a honeycomb pattern.

Silicon

It is a metalloid with atomic number 14 and atomic weight 28.09 g / mol. It is found in the earth's crust as silica (SiO ₂), sand, and quartz, as well as in various minerals and silicate clays.

Silicon is the second most abundant element in the earth's crust. It has two allotropic forms: a brown amorphous one, and a gray crystalline form, metallic luster and cubic diamond crystals.

Germanium

It is a metalloid with atomic number 32 and atomic weight 72.61 g / mol. Germanium is little known on a daily basis. It is only found as a trace in some silver and zinc minerals, as well as in some types of coal and in germanite.

It is greyish-white in color and forms a cubic and diamond crystal structure.

Tin

It is a metal with atomic number 50 and atomic weight 118.71 g / mol. Tin is a soft, moldable metal with a low melting point. It has two allotropic forms: β form, with a tetragonal crystal structure at room temperature; and form α, gray in color found at temperatures below 13 ºC.

Tin is extracted from the mineral cassiterite (SnO ₂).

Lead

It is a metal with atomic number 82 and atomic weight 207.2 g / mol. It has a face-centered crystalline structure, bluish-white color, and high toxicity to humans. Lead is found as part of the mineral galena (PbS).

Flevorian

It is a metal with atomic number 114 and an atomic weight of 287 g / mol. Flevorium is an artificial, radioactive and very short-lived element. Its properties are similar to those of noble gases, although it is possible that it is a later metal than transition metals.

characteristics

Melting point

Carbon: 3,500 ºC (diamond).

Silicon: 1,410 ºC.

Geranium: 937.4 ° C.

Tin: 231.88 ºC.

Lead: 327.50 ºC.

Boiling point

Carbon: 4,827 ºC (diamond).

Silicon: 2,355 ºC.

Germanium: 2,830 ° C.

Tin: 2,260 ºC.

Lead: 1,740 ºC.

Density

Carbon: 3.51 g / cm ³ (diamond).

Silicon: 2.33 g / cm ³.

Germanium: 5.327 g / cm ³.

Tin: 7.28 g / cm ³.

Lead: 11.343 g / cm ³.

Ionization energy

Carbon: 1,086 kJ / mol.

Silicon: 787 kJ / mol.

Germanium: 762 kJ / mol.

Tin: 709 kJ / mol.

Lead: 716 kJ / mol.

Atomic radio

Carbon: 77 pm.

Silicon: 118 pm.

Germanium: 122 pm.

Tin: 140 pm.

Lead: 175 pm.

The melting and boiling point values ​​of group 14 elements tend to decrease as their number and atomic radius increase.

This reflects a lower attractive force between the atoms as their size increases. The same tendency is observed in the ionization points of the elements of the group; the greater the distance of an electron from the nucleus, the lower the energy required for its separation.

On the contrary, as the atomic number increases, there is a tendency to increase the density of the element. This may be due to a larger number of protons and neutrons, the most massive nuclear components.

Applications

Carbon

Graphite is used in fibrous form in the manufacture of plastics. In addition, it is used in the production of pencils. The diamond is a precious jewel. Its great hardness is used in drills in the oil industry and in the tips of pencils to cut glass.

Calcium carbide is used as an intermediate in the production of the solvents carbon disulfide and carbon tetrachloride. Carbon is used in the synthesis of steel and tire fillers.

Silicon

Silicon is used as a semiconductor, as well as in various functions in the electronics industry. It has application as a lubricant and waterproofing agent. Silica (SiO ₂) is used in making ceramics and glass, as well as being a component of concrete and brick.

Silicon is used in vacuum pumps. It is essential in the nutrition of chickens and rats; although its essentiality for man is unknown. It is also a reducing agent that is used to free magnesium from its oxide.

Germanium

It was used as a semiconductor until 1950, when it was displaced by silicon; although it continues to fulfill various functions in the field of electronics. Germanium is used in radiation detectors. Germanium oxide is used in optical fibers and wide-angle lenses.

Tin

It is used to coat iron objects to protect them from rust. Tin is used in welding and in the manufacture of tinplate for packaging food. Tin chlorides are used in the reduction of iron minerals.

Tin compounds have numerous applications. For example, stannous fluoride is used in toothpastes; tin oxide in ceramics; and cobalt stannate as a cerulean blue pigment. Also, tin forms alloys like bronze and pewter.

Lead

It is used in the manufacture of car batteries; in protection against ionizing radiation; and in welding.

References

1. Shiver & Atkins. (2008). Inorganic chemistry. (Fourth edition). Mc Graw Hill.
2. Elizabeth Sproat, Jessica Lin, and Vancy Wong. (June 05, 2019). Group 14: general properties and reactions. Recovered from: chem.libretexts.org
3. Wikipedia. (2019). Carbon group recovered from: en.wikipedia.org
4. Helmenstine, Anne Marie, Ph.D. (March 21, 2019). Carbon Family of Elements. Recovered from: thoughtco.com
5. Moeller Therald. (2019). Carbon group element. Encyclopædia Britannica. Recovered from: britannica.com