- are unsaturated hydrocarbons containing at least one carbon-carbon double bond C=C between two adjacent cabon atoms.
- are hydrocarbons containing at least one triple bond.
- are different structural modifications of the same element.
- an alloy is a mixture of two or more elements, of which at least one is metal.
- or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle.
- a liquid alloy of mercury with another metal.
- atomic mass unit (amu) is an unit of measurement that is used to measure the mass of atoms and roughly equivalent to 1.67x10-27kg.
- an ion with a negative charge.
- is an electrode through which electric current flows into a polarized electrical device. A cathode is a negatively charged electrode that attracts the positive ions (cations) in a circuit or chemical reaction.
- is a substance that dissociates in water to form hydrogen (H+) ions. Arrhenius acid increases the concentration of H+ ions in an aqueous solution.
Learn more about Arrhenius theory.
- is a substance that dissociates in water to form hydroxide (OHi) ions. Arrhenius base increases the concentration of OH- ions in an aqueous solution.
Learn more about Arrhenius theory.
- the basic unit of a chemical element.
- of an element is the sum of the masses of its isotopes each multiplied by its natural abundance.
- the number of protons in an atom of an element.
- is a measure of the size of its atoms, usually the mean or typical distance from the nucleus to the boundary of the surrounding cloud of electrons.
- is a 1-, 2-, or 3-letter internationally agreed code for a chemical element, usually derived from the name of the element, often in Latin.
Only the first letter is capitalised. For example, "He" is the symbol for helium.
- a description of the building up of the elements in which he orbitals of lower energy are filled in first with the electrons and only then the orbitals of high energy are filled.
- states that the pressure of an ideal gas kept at constant temperature varies inversely with the volume of the gas. The volume of gas increases as its pressure decreases. The volume of gas decreases as its pressure increases.
- is a solution which resist changes in pH on addition of small quantities of acid or alkali or on dilution. Buffer solutions consist of weak acids and their conjugate bases or weak bases and their conjugate acids.
- is the ratio of number of moles of acid or base added to one litre of buffer to change its pH value by one unit.
- is an organic compound that consists only of carbon, hydrogen, and oxygen, usually with a hydrogen:oxygen atom ratio of 2:1.
- a continuous process by which carbon is exchanged between organisms and the environment.
- a substance that sarts or speeds up a chemical reaction without being consumed in the reaction.
- is an electrode through which electric current flows into a polarized electrical device. The anode is the positively charged electrode that attracts the negative ions (anions) in a circuit or chemical reaction.
- states that the volume of a gas at a constant pressure varies directly with its temperature (V ∝ T). This means that, at constant pressures, the volume of a given mass of an ideal gas will increase or decrease directly as its temperatures increases or decreases.
It is also known as the law of volumes.
- is the burning of a fuel and oxidant accompanied by the production heat and, usually, light.
- a chemical substance consisting of two or more different chemical elements that are chemically bonded together.
- corrosion is the deterioration of materials, usually metals, by chemical reaction with its environment.
- is a chemical bond that involves sharing a pair of electrons between atoms in a molecule.
- (Ci) is a unit of radioactivity, named after Marie Curie and equal to 37 billion Bq.
- cracking is the process whereby complex organic molecules such as kerogens or heavy hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carbon-carbon bonds in the precursors.
- is cyclic saturated hydrocarbon containing a ring of carbon-carbon bonds.
- is the distribution of electrons in the orbitals of an atom or molecule.
- is the power of an atom in a molecule to attract electrons to itself.
- a chemical element is a substance that cannot be broken down by chemical reactions.
- of a chemical is the simplest positive integer ratio of atoms present in a compound.
- a chemical reaction that absorbs heat.
- the ability to do work. Chemical energy is the potential of a chemical substance to undergo a transformation through a chemical reaction or, to transform other chemical substances.
- is a measure of the total energy of a thermodynamic system. The total enthalpy, H, of a system cannot be measured directly. Only changes in enthalpy ΔH can be measured. For processes under constant pressure, ΔH is equal to the change in the internal energy of the system, plus the work that the system has done on its surroundings.
- is the measurement of the amount of disorder in a system.
- the value of the reaction quotient for a system at equilibrium.
- is the volume of titrant required to neutralize the analyte solution.
- the vertical columns into which elements are arranged in the periodic table of elements. it is also known as a group.
- materials have a large and positive susceptibility to an external magnetic field. They exhibit a strong attraction to magnetic fields. Ferromagnetic materials have some unpaired electrons so their atoms have a net magnetic moment.
First law of thermodynamics
- states that energy can be neither created nor destroyed.
- is the splitting of an atomic nucleus into two or more lighter nuclei accompanied by energy release. The original heavy atom is termed the parent nucleus and the lighter nuclei are daughter nuclei.
- a natural fuel such as coal, oil or natural gas that formed in the geological past from the remains of living organisms..
Free energy G
- is a thermodynamic quantity that is the difference between the internal energy of a system (enthalpy) and the product of its absolute temperature and entropy of a system. Also called Gibbs free energy.
- is an atom or molecule that has at least one unpaired electron and is therefore unstable and highly reactive.
- discovered in 1985 by researchers at Rice University, are a family of carbon allotropes named after Buckminster Fuller.
- Fusion is the process of combining two or more distinct entities into a new whole. Nuclear fusion is the joining of two nuclei to form a heavier nuclei accompanied either by a release or absorption of energy.
Galvanization (or galvanisation)
- is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting.
- or γ-decay is a type of radioactive decay in which an atomic nucleus emits gamma particles or gamma rays.
- heavy water, also called as deuterium oxide or 2H2O or D2O, is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium.
- is a substance in which components are not evenly mixed. Some examples are: pizza, soup etc.
- is a substance in which components are evenly mixed. Some examples are: air, salt water etc.
- states that the electrons will occupy an open orbital before it will pair up.
- is a compound formed by the addition of water or its elements to another molecule.
- is a compound of hydrogen with another element.
- is any chemical compound that consists only of the elements carbon (C) and hydrogen (H).
- a chemical bond in which a hydrogen atom (H) of one molecule is attracted to an electronegative atom, such as fluorine, oxygen, or nitrogen atom, usually of another molecule.
- a hypothetical gas whose molecules occupy negligible space and have no interactions, and which obeys the ideal gas laws exactly.
- a chemical substance that is added in small amounts to a solution to determine the pH (acidity or alkalinity) of the solution.
- a substance that is not chemically reactive.
- a substance that blocks or decreases the rate of chemical reaction.
- is a material that will not carry any electrical current.
- an atom or group of atoms having a positive or negative electric charge by gaining or losing one or more electrons.
- is a chemical bond formed through an electrostatic attraction between two oppositely charged ions. Ionic bonds are formed between a cation, which is usually a metal, and an anion, which is usually a nonmetal.
Ionic product of water
- The equilibrium constant for the self-dissociation of water is known as ionic product for water.
- the process of producing ions.
- of an atom or molecule describes the amount of energy required to remove an electron from the atom or molecule in the gaseous state.
- are compounds that have the same chemical formula but different chemical structure.
- any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weights.
- International Union of Pure and Applied Chemistry. IUPAC is best known for its works standardizing nomenclature in chemistry and other fields of science.
- is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually shiny, malleable and ductile.
- is a chemical element some of the properties of metals and some of the properties of nonmentals.
- is the number of moles of solute dissolved in one kilogram of solvent.
- is the number of moles of solute per liter of solution.
- is the mass of one mole of a substance.
- is the amount of any substance that contains as many elementary entities (e.g., atoms, molecules, ions, electrons) as there are atoms in 12 grams of pure carbon-12.defined as the amount of any substance that contains as many elementary entities (e.g., atoms, molecules, ions, electrons) as there are atoms in 12 grams of pure carbon-12. The number of atoms in a 12g sample of carbon is 6.023 x 1023 atoms.
- is an electrically neutral group of two or more atoms held together by covalent chemical bonds. Molecule forms the smallest unit of a compound.
- the noble gases, also known as the inert gases, are located in Group VIII of the periodic table. The noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and ununoctium (Uuo).
- states that an orbital can hold a maximum of 2 electrons. These electons must have oppsite spins.
- is a horizontal row of elements on the periodic table.
- is a tabular display of the chemical elements, the elements are organized into groups and periods on the basis of their atomic numbers, electron configurations, and recurring chemical properties.
- is a a measure of acidity and alkalinity of a solution. Lower numbers indicate increasing acidity and higher numbers increasing alkalinity. Neutral pH is 7. PH stands for potential of hydrogen.
Plum pudding model
- of the atom was proposed by J. J. Thomson in 1904. He proposed that atoms have structure similar to a plum pudding, with tiny, negatively charged electrons embedded in a positively charged gel. This model was disproved by the 1909 gold foil experiment, which was interpreted by Ernest Rutherford in 1911.
- is a charged particle which has two or more atoms held together by covalent bonds.
- is an atom that has lost one or more electrons.
- the post-transition metals, also known as the poor metals, is a group of metals on the periodic table. It is to the right of the transition metals.
- is the energy of an object at rest.
- are large biological molecules consisting of one or more chains of amino acids.
- the common, stable isotope of hydrogen, having no neutrons.
- the central region of an atom containing protons and neutrons.
- is the smallest possible discrete unit of any physical property, such as energy or matter.
- is the theory that states that energy comes in small units or quanta.
- subatomic particles that make up protons and neutrons.
- the process in which energy is emitted as particles or waves.
- an atom or molecule that contains an unpaired electron.
- spontaneously emitting hign-energy particles.
- the spontaneous disintegration of unstable atomic nuclei. The energy and particles which are released during the disintegration process are called radiation.
- substance that takes part in a chemical reaction.
- a substance that reduces another substance by donating an electron or electrons.
- is the process of gaining electrons.
- is a chemical reaction in which atoms have their oxidation state changed i.e., redox reactions involve the transfer of electrons between species.
- is a chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation.
- are hydrocarbons in which all the carbon and hydrogen atoms are only linked by single bonds. They are also called as alkanes or paraffin hydrocarbons.
- is a solution in which the maximum amount of solute has been dissolved.
- is an orbit followed by electrons around an atom's nucleus. Each shell is composed of one or more subshells.
- is a state of matter, characterized by a definite volume and a definite shape.
- is the ability of a substance to dissolve into another substance.
- is a chemical compound that contains atleast three different elements.
- is the process of slow addition of one solution of a known concentration (titrant) to a known volume of another solution of unknown concentration (analyte) until the reaction reaches neutralization, which is often indicated by a color change.
- any of the metallic elements within Groups 3 through 12 in the Periodic Table.
- is a chemical bond between two chemical elements involving six bonding electrons (three pairs of electrons) instead of the usual two (one pair of electron) in a covalent single bond.
- is a radioactive isotope of hydrogen with a mass approximately three times that of the common protium isotope.
- is electromagnetic radiation which has wavelength shorter than visible light.
- Unsaturated hydrocarbons are the hydrocarbons in which not all carbon atoms have four single covalent bonds.
- is a solution which can dissolve more solute at a given temperature.
- are the electrons in the last shell or energy level of an atom.