25 terms

chemical bonds and reactions vocabulary

valence elctrons
electron that is found in the outermost shell of an atom and determines the atoms chemical properties
electron dot diagram
a model of an atom in which each dot represents a valence electron
octet rule
States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons
chemical bond
the attractive force that holds atoms or ions together
ionic bond
a chemical bond in which one atom loses an electron to form a positive ion and the other atom gains to electron to form a negative ion
a particle that is electrically charged (positive or negative)
covalent bond
a chemical bond that involves sharing a pair of electrons between atoms in a molecule
polar bond
a covalent bond in which electrons are not shared equally
non-polar bond
a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge
chemical reaction
the process in which substances undergo chemical changes that result in the formation
any solid that forms and separates from a liquid mixture
endothermic reaction
a chemical reaction accompanied by the absorption of heat
exothermic reaction
a chemical reaction accompanied by the evolution of heat
chemical equation
a representation of a chemical reaction that uses symbols to show the relationship between the reactants and the products
a chemical substance that is present at the start of a chemical reaction
a chemical substance formed as a result of a chemical reaction
A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.
conservation of mass
a fundamental principle of classical physics that matter cannot be created or destroyed in an isolated system
the process of producing a chemical compound (usually by the union of simpler chemical compounds)
(chemistry) separation of a substance into two or more substances that may differ from each other and from the original substance
the act of furnishing an equivalent person or thing in the place of another
activation energy
the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur
(chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected
any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions
a substance that slows down or stops a chemical reaction