IndietroGOB Chemistry: Reactions of Molecules
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Termini in questo insieme (26)
Atoms are not created or destroyed in chemical reactions; the total number of atoms is conserved.
A chemical equation where the number of atoms of each element is the same on both sides, achieved by adjusting coefficients.
A unit representing 6.022 x 1023 atoms or molecules, also called Avogadro's number.
Use of reaction coefficients to calculate amounts of reactants and products, usually in moles, based on balanced equations.
Loss of electrons or increase in oxidation number; often involves gaining bonds to oxygen or losing bonds to hydrogen.
Gain of electrons or decrease in oxidation number; often involves losing bonds to oxygen or gaining bonds to hydrogen.
A reaction involving simultaneous oxidation and reduction; electrons lost by one species are gained by another.
Ox # of uncombined atom = 0; monatomic ion = charge; Group IA = +1; Group IIA = +2; H = +1; O = -2 (except peroxides); sum equals compound charge.
Thermal energy released or absorbed during a reaction, measured per mole of reaction coefficients.
Reaction that releases heat to surroundings; has a negative ΔH.
Reaction that absorbs heat from surroundings; has a positive ΔH.
Measure of disorder in a system; increases with more disorder and higher temperature.
A reaction that proceeds without external input; characterized by negative free energy change (ΔG).
Energy available to do work; calculated as \(\Delta G = \Delta H - T\Delta S\).
Reaction that releases free energy; has negative ΔG and is spontaneous.
Reaction that requires free energy input; has positive ΔG and is non-spontaneous.
Minimum energy required to start a reaction; determines reaction rate.
Speed of a reaction measured by change in concentration of reactants or products over time.
Higher temperature, higher concentration, and presence of a catalyst increase reaction rate.
Substance that lowers activation energy and speeds up reaction rate without being consumed.
State where forward and reverse reaction rates are equal; concentrations remain constant.
Ratio of product concentrations to reactant concentrations at equilibrium; indicates reaction direction.
When a system at equilibrium is stressed, it shifts to relieve the stress by favoring forward or reverse reaction.
Increasing temperature favors endothermic direction; decreasing temperature favors exothermic direction.
Adding reactants or removing products shifts equilibrium forward; adding products or removing reactants shifts it backward.
Catalysts speed up reaching equilibrium but do not change the equilibrium constant or position.