Term | Definition |
atom | The building blocks of matter. |
compound | A pure substance formed when two or more different elements combine. |
covalent bond | The chemical bond that forms when electrons are shared. |
electron | Negative charged particles that are located outside the nucleus. |
element | A pure substance that cannot be broken down into other substances by physical or chemical means. |
ion | An atom that has lost or gained one or more electrons. |
ionic bond | An electrical attaction between two oppositely charged atoms or groups of atoms. |
isotope | Atoms of the same element that have different numbers of neutrons. |
molecule | A compound in which the atoms are held together by covalent bonds. |
neutron | Particles that have no charge. |
nucleus | A distinct central organelle that contains the cells genetic material in the form of DNA. |
proton | positively charged particles.. |
van der Waals force | The Dutch physicist Johannes van der Waals who first described the phenormenon. |
activation energy | The minimum amouhnt of energy needed for reactants to form products in a chemical reaction. |
active site | The specific location where a substrate binds on an enzyme. |
catalyst | A substance that lowers the activation energy needed to start a chemical reaction. |
chemical reaction | The process by which atoms or groups of atoms in a substance are recorganized by different substances. |
enzyme | The biological catalysts that speed up the rate of chemical reations in biological processes. |
product | The substances formed during the reaction, are on the right side of the arrow. |
reactant | The starting substances on the left side of the arrow. |
substrate | The reatants that bind to the enzyme. |
acid | Substances that release hydrogen ions when dissvolved in water. |
base | Similarly substances that release hydroxide ions (OH-) when dissolved in water |
buffer | Mixtures that can react with acids or bases to keep the ph within a particular range. |
hydrogen bond | A weak interaction involving a hydrogen atom and a fluorine,oxygen ,or nitrogen atom. |
mixture | A combination of two or more substances in which each substance retains its individual characteristics and properties. |
pH | The measure of concentration of H+ in a solution |
polar molecule | Molecules that have an unequal distribution charges. |
solute | The substance that dissolves in the solent. |
solution | Another name for a homogeneous mixture. |
solvent | A substance in which another substance is dissolved. |
amino acid | Small compounds that are made of carbon,nitrogen,oxygen,hydrogen,and sometimes sulfur. |
carbohydrate | Compounds composed of carbon,hydrogen,and oxygen in a ratio of one oxygen and two hydrogen atoms for each carbon atom. |
lipid | Molecules made mostly of carbon and hydrogen that make up the fats,oils and waxes. |
macromolecule | Large molecules that are formed by joing smaller organic molecules together. |
nucleic acid | The fourth group of biological macromolecules are nucleic acids. |
nucleotide | Nucleic acids are made of smaller repeating subunits composed of carbon,nitrogen ,oxygen phosphorus,and hydrogen atoms. |
polymer | Molecules made from repeating units of identical or nearly identical compounds called monorners that are linked together by series of covalent bonds. |
protein | A compound made of small compounds that are made of small carbon compounds. |