Chemistry Flashcards
acidic solution
a solution that contains more hydrogen ions than hydroxide ions
activation energy
energy that must be added to start a chemical reaction; the smallest amount of energy needed to convert a stable, normal molecule into a reactive molecule
anion
atom or group of atoms with a negative electrical charge
atomic mass
sum of the number of protons and neutrons in the nucleus of an atom
atomic number
number of protons in the nucleus
Avogadro’s number
number of particles in a mole: 6.02 x 10(23)
basic solution
a solution that contains more hydroxide ions than hydrogen ions
catalyst
substance that lowers the activation energy of a reaction and therefore speeds up the resulting rate
cation
atom or group of atoms with a positive electrical charge
chemical reaction
process by which atoms of substances become rearranged to form new substances
Equation:
Reactant A + Reactant B = Product C + Product D
colligative properties
characteristics of a solution that are a function of concentration
covalent bond
the chemical bond formed when two atoms share electrons
decomposition reaction
a reaction in which a single compound breaks down into two or more elements or compounds
AB = A + B
double-displacement reaction
a reaction in which two different ionic compounds exchange ions
AB + CD = AD + CB
electron
negatively charged particle in motion surrounding the nucleus of an atom
endothermic
reaction or process that requires energy and usually feels cold to the touch
energy flow
the release of stored energy through chemical changes
exothermic
process or reaction that releases energy and usually produces heat
extensive properties (extrinsic)
properties that depend on the amount of matter present
group
column on the periodic table of elements with common outer shell configurations and characteristics
heterogeneous mixture
mixture in which substances that retain their distinct characteristics and do not blend completely
homogeneous mixtures
mixture in which two or more distinct substances have a constant composition within a sample
intensive property (intrinsic)
characteristic of a substance that is independent of the amount of material present
ion
atom with an unbalanced number of positive and negative charges
ionic bond
chemical bond formed by transfer of one or more electrons between atoms
isotope
form of an element with differing numbers of neutrons but the same number of protons
mass number
the sum of the number of protons and the number of neutrons
molar mass
mass of one mole of a pure substance
mole
a convenient measure that identifies the number of particles, 6.02 x 10(23), and is equal t the number of grams of a substance from the atomic mass on the periodic table
neutralization
a reaction between a base and an acid that produces a neutral (ph = 7) solution
when acids and bases react together to form salt and water
Equation:double displacement between and acid(HX) and base(YOH)
HX + YOH = YX + HOH(H2O)
nonpolar
substance that has an equal distribution of electrons between atoms or symmetrical shape so that no part of the molecule is more positive or negative
nuclear reaction
change that affects the nucleus of an atom
periodic table
chart that organizes the elements based on their properties