15 terms

7th Grade Science: Classes, Energy, and pH of Chemical Reactions

Vocabulary list for the 7th grade chemical experimental design module
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chemical bond
An attractive force that holds together the atoms in a molecule.
covalent bond
chemical bond formed when two atoms share one or more electrons
ionic bond
chemical bond formed when one atom gains and a second atom loses electrons
single displacement
a reaction in which one element takes the place of another element in a compound
double displacement
a reaction where 2 reactants exchange places
decomposition reaction
a reaction where the compound breaks down to form two or more simpler substances
synthesis reaction
a reaction in which two or more substances combine to form a new compound
endothermic
a chemical reaction that absorbs energy
exothermic
A chemical reaction that releases energy
precipitate
a solid that forms as a result of mixing two solutions
acid
a chemical substance that is corrosive is tart or sour-tasting and has a pH of less than 7
base
a chemical substance that feel slippery when dissolved in water, is bitter tasting, and has a pH greater than 7
indicator
a compound that changes color when placed in an acid or base
pH
a measure of how acid or basic a solution is
catalyst
substance that speeds up the rate of a chemical reaction