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Aim: How do chemists use redox reactions to produce electricity?. How are oxidation numbers assigned? How to determine if a particle is oxidized or reduced from an oxidation-reduction reaction? 3 . Distinguish between an oxidizing agent and
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Aim: How do chemists use redoxreactions to produce electricity? How are oxidation numbers assigned? How to determine if a particle is oxidized or reduced from an oxidation-reduction reaction? 3. Distinguish between an oxidizing agent and reducing agent.4. How is the process of oxidation/reduction utilized in electrolysis, electroplating and electrochemical cells?5. Write and interpret half-cell reaction equations.
Aim: How do chemists use redoxreactions to produce electricity? • An electrochemical cell can be either voltaic or electrolytic. In an electrochemical cell, oxidation occurs at the anode and reduction at the cathode. • A voltaic cell spontaneously converts chemical energy to electrical energy. • An electrolytic cell requires electrical energy to produce a chemical change. This process is known as electrolysis.
Aim: How do chemists use redoxreactions to produceelectricity? • Salt bridge- provides a path for the flow of ions between two beakers. • Wire- provides a path for electrons lost during oxidation at the anode. • What does LEO GER mean? • What does AN OX and RED CAT mean?
Aim: How do chemists use redoxreactions to produceelectricity? Voltaic cell- electrochemical cell in which a spontaneous chemical reaction produces a flow of electrons. Anode- site of oxidation. Cathode- site of reduction.
Aim: How do chemists use redoxreactions to produce electricity? • Compare and contrast volatic/electrochemcial cells with electrolytic cells
Aim: How do chemists use redoxreactions to produce electricity? Comparison of voltaic with electrolytic: • Both use redox reactions. • The anode is the site of oxidation. • The cathode is the site of reduction. • The electrons flow through the wire from anode to cathode.
Aim: How do chemists use redoxreactions to produce electricity? Contrast voltaic with electrolytic cells: • Voltaic/electrochemcial cells have spontaneous redox reactions; the electrolytic cell is non-spontaneous (needs a power source such as a battery.) • In a voltaic cell the anode is negative and the cathode is positive; In an electrolytic cell the anode is positive and the cathode is negative.