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a measure of the amount of matter in an object; a fundamental property of an object that is not affected by the forces that act on the object, such as the gravitational force
a substance that cannot be separated or broken down into simpler substances by chemical means; all atoms of an element have the same atomic number
a subatomic particle that has a positive charge and that is located in the nucleus of an atom; the number of protons in the nucleus is the atomic number, which determines the identity of an element
the number of protons in the nucleus of an atom; the atomic number is the same for all atoms of an element
an atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different atomic mass)
a group of atoms that are held together by chemical forces; a molecule is the smallest unit of matter that can exist by itself and retain all of a substance's chemical properties
an atom, radical, or molecule that has gained or lost one or more electrons and has a negative or positive charge
the attractive force between oppositely charged ions, which form when electrons are transferred from one atom to another
the intermolecular force occurring when a hydrogen atom that is bonded to a highly electronegative atom of one molecule is attracted to two unshared electrons of another molecule
the attractive force between two bodies of different substances that are in contact with each other
the amount of a particular substance in a given quantity of a mixture, solution, or ore
any compound that increases the number of hydronium ions when dissolved in water; acids turn blue litmus paper red and react with bases and some metals to form salts
any compound that increases the number of hydroxide ions when dissolved in water; bases turn red litmus paper blue and react with acids to form salts
a value that is used to express the acidity or alkalinity (basicity) of a system; each whole number on the scale indicates a tenfold change in acidity; a pH of 7 is neutral, a pH of less than 7 is acidic, and a pH of greater than 7 is basic
a solution made from a weak acid and its conjugate base that neutralizes small amounts of acids or bases added to it
the process by which one or more substances change to produce one or more different substances
a substance that changes the rate of a chemical reaction without being consumed or changed significantly
a type of protein or RNA molecule that speeds up metabolic reactions in plant and animals without being permanently changed or destroyed
a reaction in which electrons are transferred between atoms; also known as oxidation reduction reaction
chemical reaction in which a reactant loses one or more electrons such that the reactant becomes a more positive charge
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