Chemistry: Oxidation and Reduction

Oxidation and Reduction

• Oxidation: loss of electrons by a species, resulting in an increase in oxidation state
• Reduction: gain of electrons by a species, resulting in a decrease in oxidation state
• Oxidation Number: a number assigned to an atom in a molecule to indicate its degree of oxidation
• Redox Reactions: chemical reactions involving oxidation and reduction, often accompanied by the transfer of electrons

Electroplating

• Electroplating: a process in which a thin layer of a material (e.g., metal) is deposited onto the surface of another material using an electric current
• Electrolytic Deposition: the process of depositing a substance onto an electrode using an electric current
• Uses: decorative plating, protective coating, and to enhance the mechanical properties of materials

Electrolytic Cells

• Electrolytic Cell: an electrochemical cell that uses an external electrical energy source to drive a chemical reaction
• Components: an anode, a cathode, and an electrolyte
• Reaction: oxidation occurs at the anode, and reduction occurs at the cathode
• Types: voltaic cells, electrolytic cells, and fuel cells

Industrial Applications

• Chlor-Alkali Process: the production of chlorine and sodium hydroxide through the electrolysis of sodium chloride (common salt)
• Aluminum Production: the extraction of aluminum from its ores through electrolysis
• Water Purification: electrolysis used to remove impurities and minerals from water
• Hydrogen Production: the production of hydrogen gas through the electrolysis of water, used as a clean energy source

Oxidation and Reduction

• Oxidation is the loss of electrons by a species, resulting in an increase in oxidation state
• Reduction is the gain of electrons by a species, resulting in a decrease in oxidation state
• Oxidation number is a number assigned to an atom in a molecule to indicate its degree of oxidation
• Redox reactions are chemical reactions involving oxidation and reduction, often accompanied by the transfer of electrons

Electroplating

• Electroplating is a process in which a thin layer of a material (e.g., metal) is deposited onto the surface of another material using an electric current
• Electrolytic deposition is the process of depositing a substance onto an electrode using an electric current
• Electroplating is used for decorative plating, protective coating, and to enhance the mechanical properties of materials

Electrolytic Cells

• An electrolytic cell is an electrochemical cell that uses an external electrical energy source to drive a chemical reaction
• Components of an electrolytic cell include an anode, a cathode, and an electrolyte
• Oxidation occurs at the anode, and reduction occurs at the cathode
• Types of electrolytic cells include voltaic cells, electrolytic cells, and fuel cells

Industrial Applications

• The chlor-alkali process involves the production of chlorine and sodium hydroxide through the electrolysis of sodium chloride (common salt)
• Aluminum production involves the extraction of aluminum from its ores through electrolysis
• Electrolysis is used in water purification to remove impurities and minerals from water
• Hydrogen production involves the production of hydrogen gas through the electrolysis of water, used as a clean energy source