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H

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half-reaction

A portion of an oxidation-reduction reaction involving only the oxidation or only the reduction portion; useful in balancing oxidation-reduction reactions and assigning electrode potentials.


Decomposition Reactions ... Electrolysis of Aqueous Solutions ... HCl ... Half-reaction at the Anode, Cathode ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... NaOH ... Half-reaction at the Anode, Cathode ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... NaCl ... Half-reaction at the Anode, Cathode ...

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heat

Energy transferred as a result of a temperature difference; a form of energy stored in the movement of atomic-sized particles.


Combination Reactions ... Reaction of Sodium and Chlorine ...
Decomposition Reactions ... Ammonium Dichromate Volcano ...
Single Exchange Reactions ... Thermite Reaction ... Movie ...

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heat of reaction

The heat absorbed as a reaction occurs.


Combination Reactions ... Reaction of Sodium and Chlorine ...
Decomposition Reactions ... Ammonium Dichromate Volcano ...
Single Exchange Reactions ... Thermite Reaction ... Movie ...

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helium

An element in the periodic table with symbol He, atomic number 2, and atomic weight 4.003


Gases ... Effusion of Gases ... Helium He ...
Gases ... Effusion of Gases ... Methane ...

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hydrogen

An element in the periodic table with symbol H, atomic number 1, and atomic weight 1.008


Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Hydrogen alone ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Hydrogen plus some Oxygen ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Hydrogen plus more Oxygen ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Molecular Representation ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Equivalent Amounts ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Excess Hydrogen ...
Stoichiometry ... Exploding Soap Bubbles: Hydrogen + Oxygen ... Excess Oxygen ...
Stoichiometry ... Acid-Base Titrations and Animation ... Acid-Base Titration Animation ...
Combination Reactions ... Hydrogen + Chlorine Cannon ... Hydrogen + Chlorine Animation ...
Combination Reactions ... Oxidation and Reduction of Copper ...
Decomposition Reactions ... Electrolysis of Water ... Sulfuric Acid Solution ...
Decomposition Reactions ... Electrolysis of Water ... Animation of Electrolysis ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... HCl ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... NaOH ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... NaCl ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... tin(IV) chloride ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... sodium nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... magnesium nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... aluminum nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... potassium nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... calcium nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... cobalt(II) nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... nickel(II) nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... strontium nitrate ...
Decomposition Reactions ... Electrolysis of Aqueous Solutions ... barium nitrate ...
Single Exchange Reactions ... Water Gas Reaction ...
Single Exchange Reactions ... Oxidation and Reduction of Copper ...
Double Exchange Reactions ... Precipitation Reactions ... sodium hydroxide and copper(II) nitrate ... Molecular Representation ...
Double Exchange Reactions ... Acid-Base Titrations and Animation ... Acid-Base Titration Animation ...

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© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.