Electrolytes and Non-electrolytes

1. Electrolyte are compound that conduct electricity in a molten state or in an aqueous solution and are decomposed to their constitute elements in the process
2. All electrolyte contain freely moving ions that conduct electricity
3. Non-electrolytes are substance that do not conduct electricity even in a molten state or in an aqueous solution
4. All non-electrolytes do not contain mobile ions. Covalent compounds usually do not conduct electricity because they are made up of neutral molecules.
5. A conductor is a substance which conduct electricity but does not change chemically during the conduction

Electrolysis of Molten Compound

1. The conductivity of electricity in an electrolyte , leading to its decomposition to its constituent elements is called electrolysis
2. An electrolytic cell consists of electrodes, electrolytes and the sources of electricity is used to produced a chemical reaction
3. There are three processes in electrolysis

a)     Movement of electron in the external circuit

b)     Movement of ions in the electrolyte

c)     Discharge of ions at the surface of electrodes.

4. An electrode which connected to the positive terminal of batteries is called the anode. An electrode which connected to the negative terminal of a battery is called the cathode. Positively charged ions ( cations ) are attracted by the cathode and negatively charged ions (anion ) are attracted by the anode.
5. During electrolysis of molten electrolyte, positive ion move towards cathodes and are discharged by gaining electrons from the cathode. Negative ions move towards the anode and are discharged by losing electrons to the anode.
6. Electrolysis of molten ionic compound produces metals at the cathode and non-metals at the anode.

Electrolysis of Aqueous solution

1. The products of electrolysis of an aqueous solution at the electrode depend on three factors
1. Position of ions in electrochemical series
2. Concentration of the ions in the electrolyte
3. Nature of electrode

Electrolysis in Industries

1. Application of electrolysis in industry include:
1. Extraction of reactive metals
2. Purification of metal
3. Electroplating of metal

Voltaic Cell

1. A voltaic cell produces electrical energy by mean of chemical reaction. It converts chemical energy to electrical energy. Its is also know as an electrochemical cell or a galvanic cell
2. A simple voltaic cell consists of two different connected metals in contact with electrolytes. Metal that are more electropositive are made negative electrodes the less electropositive metal are made the positive electrodes.
3. A Daniell cell is a zinc-copper cell. There are two structure of Daniell cells
1. A Daniell cell with a salt bridge
2. A Daniell cell with porous pot

Electrochemical Series

1. The electrochemical series is a list of metal arranged in descending order of their atoms tendency to lose electrons to form positive ions. The more electropositive metals are placed higher up in the series
2. the electrochemical series is used to
1. predict the displacement reaction
2. determine the positive and negative terminal of an electrochemical cell
3. compare the voltage of electrochemical cell

EXERCISE

1. “Covalent compound is a non-electrolyte whereas an ionic compound is”

Describe an experiment to prove the above statement. You answer should include the following:

1. Aim
2. Hypothesis
3. State all variable involved
4. Apparatus and chemical used
5. Procedure of experiment
6. Tabulation of result

2. A chemical cell can be set up by immerse two different metal electrode in an electrolyte. “The further the distance between the two metal, the higher the voltage of the cell” You are given zinc, iron, copper electrode and other chemical needed. Describe an experiment to prove the above statement. You answer should include:
1. Problem statement
2. Hypothesis
3. Apparatus and chemical used
4. Procedure of experiment
5. Tabulation of result
6. Conclusion

3.  
1. You are given four metals P, Q, R and S and its salt solution, P nitrate, Q nitrate, R nitrate and S nitrate. Describe an experiment to prove that the electro- positivity of the metal decreases in the order R,P,S,Q
2. Explain how you can electroplate an iron spoon with silver metal