Electrolysis Simulation

THE ELECTROLYSIS CELL

An electrolytic cell is a cell consisting of two electrodes (anode and cathode) immersed in an electrolyte for carrying out electrolysis, a direct electric current is passed through the electrolyte from an external source. Molten salts and aqueous solution of ionic compounds are electrolyte commonly need in electrolysis. Anode is the electrode that connected to the positive terminal of the battery. At this electrode, anions was release their electron. Cathode is the electrode that connected to the negative terminal of the battery. At this electrode, cation was received an electrons. Factor affecting the selective discharge of ions When more than one type of cation or anions is present in a solution, only one cation and anion is preferentially selected for discharged. The selective discharge of ions depends on three factors. a) The concentration of the ion in the electrolyte. b) The standard electrode potential of the ion (the position of the metal in the

electrochemical series) c) The type of electrode (active or inert) used. 1

Electrolysis is used for effluent treatment. Heavy metal ions from manufacturing process that are found in effluent can be removed by electrolysis.

Spontaneous reaction is known as, if a reaction of its own accord when the reactants are mixed at room temperature and pressure. Non-spontaneous reaction is known as, if the reaction does not occur of its own accord at room conditions.

ENGAGE 2

You are given the picture as shown below: Electric current was supply to the water.

1. What do you observe? 2. What happen on the wire?

3. How this happen? 4. How this could apply in daily life?

EMPOWER 3

Steps 1. Electrolysis is a method of using an electric current to drive an otherwise non-

spontaneous chemical reaction. Electrolysis is commercially highly important as a stage in the separation of elements from naturally-occurring sources such as ores using an electrolytic cell. 2. Electrolysis Cell is cell that use electric power through itself to produce chemistry reaction. 3. Oxidation: A process in which a substance loses one or more electrons 4. Reduction: A process in which a substance gains one or more electrons 5. Anode is the electrode that connected to the positive terminal of battery 6. Cathodeis the electrode that connected to the negative terminal of battery 7. Log on the web site to observe the animation to answer the question.

http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/simDownload/inde x4.html#electrochem

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Results:

Electrolysis of Ni (NO3)2

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Electrolysis of Fe(NO3)

Electrolysis of Cu (NO3)2

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Electrolysis of Ag (NO3)2 Question 1. What the reaction at the anode and cathode in the process electrolysis of Nikel(II) Nitrate? 2. Why the mass off anode is reduce in the anode? 3. Why the mass off cathode is increase in cathode?

Answer: Cathode:

Ni2+ (aq) + 2e-

Anode:

Ni(s)

Ni(s) Ni2+ (aq) + 2e-

2. Because the cation (Ni2+) was remove from the anode make the mass of electrode is reduce. 3. Because the cathode electrode was accepted the cation (Ni 2+).That make the mass off cathode is increase. 7

ENHANCE

Figure 1 8

Activity 2  http://www.chem.iastate.edu/ChemEdGroup/GREENBOWE/sections/projectfolder/flashfiles/elec troChem/electrolysis10.html According to figure 1 a) Will nickel metal spontaneously react with aqueous nickel (II) nitrate?  b)  Predict what will happen when the power is turned on?  c)  Identify the metal used for each electrode? d) Indicate the direction of the flow of electrons in the wire? e) Indicate what will happen at each electrode? f) Identify the anode and the cathode? g) Write the half­reactions and full­reaction that will occur?

Figure 2 According to figure 2

a) Will nickel metal spontaneously react with aqueous iron (II) nitrate?  b)  Indicate the direction of the flow of electrons in the wire?  c) Indicate what will happen at each electrode? 9

d) Identify the metal used for each electrode? e) Identify the anode and the cathode? f) Write the half­reactions and full reaction with the balanced chemical equation?

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