amount of substance definition biology
Amount of substance is a standards-defined quantity that measures the size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles.It is sometimes referred to as chemical amount.he mole is defined as the amount of substance that contains an equal number of elementary entities as there are atoms in 12 g of the isotope carbon-12. Substance. Definition. noun, plural:substances. (1) The physical matter, material or that of which an organ or body consists. (2) (chemistry) A material, matter or that which has definite chemical composition and distinct properties.(3) The most vital or essential part of something. (4) Drugs, as in substance abuse.oun, plural:substances. (1) The physical matter, material or that of which an organ or body consists. (2) (chemistry) A material, matter or that which has definite chemical composition and distinct properties. (3) The most vital or essential part of something. (4) Drugs, as in substance abuse. The SI unit for amount of substance is the mole. It has the unit symbol mol. The mole is defined as the amount of substance that contains an equal number of elementary entities as there are atoms in 12 g of the isotope carbon-12.This number is called Avogadro's number and has the value 7023602214085700000♠6.022140857(74)×1023.he mole is defined as the amount of substance that contains an equal number of elementary entities as there are atoms in 12 g of the isotope carbon-12. Activation energy. Definition. noun. The amount of energy (in joules) needed to convert all the molecules in one mole of a reacting substance from a ground state to the transition state intermediate.Supplement. The activation energy is a term coined by the Swedish scientist, Svante Arrhenius in 1889.ctivation energy. Definition. noun. The amount of energy (in joules) needed to convert all the molecules in one mole of a reacting substance from a ground state to the transition state intermediate. Supplement. In biology, the term substance is used to refer to the material constituting an organ, e.g. ground substance or spongy substance. In chemistry, all compounds are substances but not all substances are compounds since pure elements are also chemical substances.oun, plural:substances. (1) The physical matter, material or that of which an organ or body consists. (2) (chemistry) A material, matter or that which has definite chemical composition and distinct properties. (3) The most vital or essential part of something. (4) Drugs, as in substance abuse. As an example, the radioactive decay of carbon-14 is exponential with a half-life of 5730 years. A quantity of carbon-14 will decay to half of its original amount (on average) after 5730 years, regardless of how big or small the original quantity was.alf-life (t1⁄2) is the amount of time required for the amount of something to fall to half its initial value. The term is very commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay, but it is also used more generally for discussing any type of exponential decay. 1 The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12; its symbol is mol.he SI unit of amount of substance is the mole (mol): 1  The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12; its symbol is mol. Some Common Indicators 1. Litmus paper turns red or a shade of red in acids. Litmus turns blue or a shade of blue in bases. It is important to place a few drops or a small amount of the substance to be tested on the litmus paper when testing it.Do not dip the litmus paper in the substance to be tested. A paper which provides a more specific indication of the pH level of a substance is pH paper.ome Common Indicators 1. Litmus paper turns red or a shade of red in acids. Litmus turns blue or a shade of blue in bases. It is important to place a few drops or a small amount of the substance to be tested on the litmus paper when testing it. Extensive physical properties are those that are dependent on the amount of the substance present. Intensive physical properties are those that do not depend on the amount of the substance present. This means they will be the same whether you have one gram or one thousand kilograms of the substance.Density is a physical property that is determined by dividing the mass of a given amount of a substance by its volume. It is often reported in units of g/mL, which means 'grams per milliliter'.Density is an intensive property because the density of a pure substance will be the same no matter how much of it you have.his means they will be the same whether you have one gram or one thousand kilograms of the substance. Density is a physical property that is determined by dividing the mass of a given amount of a substance by its volume. It is often reported in units of g/mL, which means 'grams per milliliter'. The mole is that amount of substance of a system that contains exactly 6.022 141 79 x 1023 specified elementary entities, which may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.he mole is that amount of substance that contains the same number of elementary entities as there are atoms in 12 g of carbon 12. When the mole is used, the entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.
Amount of substance is a standards-defined quantity that measures the size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles.