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There are mines of elemental carbon such as graphite. It is the most stable form of elemental carbon at 25°C, under 1 atm (Section 3.7). A second form of pure or nearly pure elemental carbon is represented by diamonds (Section 3.12). Other forms of elemental carbon are produced by combustion or heat treatment of wood (Section 3.6), bio-polymers such as paper, cotton (cellulose), or synthetic polymers such as viscose (Section 11.10.1) and polyacrylonitrile (Section 8.2.7). Nanoparticles such as graphene (Section 3.7), fullerenes (Section 3.8), nanotubes (Section 3.9), and quantum dots of carbon (Section 3.10) are available that find biomedical applications and are used in the manufacture of nanometric objects useful for electronics, optoelectronics, photophysics, energy and the environment protection. Nanoparticles must be handled with care as they can be toxic…

In the atmosphere carbon dioxide (also called carbonic anhydride: CO₂) is the most abundant form of carbon (Section 4.1). In the lithosphere and hydrosphere carbon is found in the form of carbonates ${(\text{CO}}_3^{2-})$ and bicarbonates (hydrogen carbonates: ${\text{HCO}}_3^{-})$, bound to mono-cations such as sodium Na⁺, potassium, K⁺, ammonium cation, ${\text{NH}}_4^{+}$, or dications such as calcium Ca²⁺ and magnesium Mg²⁺. Carbon dioxide, carbonates and bicarbonates are mineral carbon compounds (Sections 4.3, 4.5 and 4.6). These compounds are described, their uses and their most important properties are presented. This exercise will allow us to introduce fundamental notions about chemical equilibria (Section 4.2).

Natural gas consists mainly of methane (CH₄) and ethane (CH₃CH₃) and other hydrocarbons in small quantities. Depending on the source it may also contain CO₂, nitrogen (N₂), hydrogen sulfide (H₂S) and helium (He). It is very abundant and its combustion contributes to the increase of the CO₂ content in the biosphere. Natural gas is a non-renewable fuel (Section 5.1). It is widely used to produce electricity, heat, chemicals including hydrogen, and hydrocarbons (liquid fuels) and as a fuel for motor vehicles…

The sun is the only source of renewable energy available to us, if geothermal energy is not taken into account. In the form of radiation (UV light, visible light, infrared light, Section 1.1) it sends us annually 178,000 terawatts (1 TW = 10¹² W; unit of power 1 W = 1 J s^–1 = 859.85 calories per hour), that is to say 15,000 times the energy consumed annually by humanity. Only 0.1% of the solar energy received by planet Earth is converted into plant biomass, i.e. 100 × 10⁹ tons per year which corresponds to ca. 180 × 10⁹ tons per year of CO₂ captured from the atmosphere. This CO₂ returns to the biosphere after the death of the plants. Consumption of fossil carbon emits ca. 35 × 10⁹ tons of CO₂ yearly. Biomass is the material produced by all living organisms (plants, animals, microorganisms, fungi)…

Syngas is a mixture of carbon monoxide (CO) and molecular hydrogen (H₂) that can be converted into a host of industrial feedstocks including fuels such as gasoline, fuel oil and kerosene. We examine what are the most abundant sources of these two gases and describe some important transformations that continue to fascinate scientists because, with a reactant as simple as CO, which contains only one carbon atom, catalysts allow to condense it with H₂ and to form C–C bonds even though all oligomers of the (CO)_n type (n = 2, 3, …) are kinetically and thermodynamically unstable. Let us recall here that thanks to photosynthesis, Nature builds C–C bonds (e.g. D-glucose) from CO₂ and H₂O and solar light! (Section 1.4.2, reaction (1.8), Figure 1.10)…