The Energy Conservation Act states that energy cannot be generated or destroyed. It can only change from one form to another. The law of conservation of matter states that in any given system that is closed to the transfer of matter, the amount of matter in the system remains constant. As early as 520 BC. Jain philosophy, a non-creationist philosophy based on the teachings of Mahavira,[4] stated that the universe and its components, such as matter, cannot be destroyed or created. The Jain text Tattvarthasutra (2nd century AD) states that a substance is permanent, but its modes of appearance are characterized by creation and destruction. [5] The law of conservation of mass applies because natural elements are very stable under the conditions of the Earth`s surface. Most elements come from fusion reactions that only occur in stars or supernovae. Therefore, in the everyday world of the earth, from the top of the highest mountain to the depths of the deepest ocean, atoms are not converted into other elements during chemical reactions.
For this reason, the individual atoms that make up living and non-living matter are very old and each atom has a history. A single atom of a biologically important element such as carbon could have been buried as coal for 65 million years before being burned in a power plant, followed by two decades in the Earth`s atmosphere before being dissolved in the ocean, then ingested by an algal cell consumed by a copepod before being inhaled and re-entering the Earth`s atmosphere (Figure 1). The atom itself is neither created nor destroyed, but circulates between chemical compounds. Ecologists can apply the law of mass conservation to elemental cycle analysis by performing a mass balance. These analyses are as important to the advancement of ecology as Lavoisier`s discoveries are to chemistry. The conservation of relativistic and invariant mass applies even to particle systems produced by pair production, where the energy for new particles may come from the kinetic energy of other particles or from one or more photons as part of a system that includes other particles in addition to one photon. Again, neither the relativistic mass nor the invariant mass of completely closed (i.e. isolated) systems change when new particles are created. However, various inertial observers will disagree on the value of this conserved mass when it comes to relativistic mass (i.e. relativistic mass is conserved, but not invariant). However, all observers agree on the value of the conserved mass if the measured mass is the invariant mass (i.e. the invariant mass is both conserved and invariant).
where one molecule of methane (CH4) and two molecules of oxygen of O2 are converted into one molecule of carbon dioxide (CO2) and two molecules of water (H2O). The number of molecules resulting from the reaction can be derived from the principle of conservation of mass, since initially four hydrogen atoms, 4 oxygen atoms and one carbon atom are present (as well as in the final state); Therefore, the number of water molecules produced must be exactly two carbon dioxide produced per molecule. This principle is why teachers put so much effort into teaching the principle of stoichiometry, and why teachers insist that chemical equations be balanced. If the equation is unbalanced, then we know that it does not reflect chemical reality, but real reality. The law of conservation of mass and the analogous law of conservation of energy were eventually replaced by a more general principle known as mass-energy equivalence. Special relativity also redefines the concept of mass and energy, which can be used interchangeably and are defined in relation to the frame of reference. For consistency, several quantities had to be defined, such as the rest mass of a particle (mass in the rest system of the particle) and the relativistic mass (in another frame). The latter term is generally used less frequently. Human agricultural systems can also be analysed using an ecosystem mass balance approach. Traditional farming practices emphasized efficiency, with most production remaining on the farm – livestock feed was produced on the farm, food for farming families was produced on the farm, and plant and animal waste was composted for use as fertilizer on the farm.
As a result, the material cycle within the agricultural “ecosystem” was important relative to the inputs and outputs of the system (a relatively closed ecosystem). In contrast, modern industrial agriculture emphasizes maximizing yields rather than efficiency. Farmers import fertilizer in large quantities (often much more than the quantities that plants can use) and manufacture and export raw materials.