Electrochemistry

ELECTROCHEMISTRY

SCIENTIFIC CONCEPT Siries of Electrochemistry Siries of Electrochemistry is the position of the metal to compare the tendency to form ions.

K+ Na+ Ca2+ Mg2+ Al3+ Zn2+ Fe2+ Sn2+ Pb2+ H+ Cu2+ Hg+ Ag+ Au+

tendency of metal to form cation increase (more electropositive)

In electrochemistry siries, metal that has more tendency to become ions is negative terminal and the metal has less tendency to become ions is a positive terminal of electrochemical cell.

UNIQUE FEATURE OF ACTIVITY

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This activity requires students to build and compare position of metal in electrochemistry siries. The unique feature of using spreadsheets are: •

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This data can be manipulated easily, for example the students know the position metal in siries of electrochemisty when the metal that high tendency to become ions is place in the above siries of electrochemistry. Data displayed in a systematis manner, save time in drawing graphs, show relationship between the most electropositif metal and their position in electrochemistry siries. Students will discover that a spreadsheet can be used to process data. Allow the students to do more important things such as analyzing the data and graph.

ENGAGE

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Why this lamp aflame? What cause the lamp aflame when we swith on it? How could this happen?

EMPOWER 1. Students plan an experiment to determine the position of metals in the series of electrochemistr 3

APPARATUS AND MATERIAL 2. They are given the following apparatus 1. Voltmeter 2. Beaker 3. Filter paper 4. A strip of magnesium, zink, aluminium, copper, ferum 5. Copper(II)sulphate 0.5 mol dm-3 6. Aluminium sulphate 0.5 M 7. Magnesium sulphate 0.5 M 8. Ferum(II) sulphate 0.5 M 9. Potassium nitrate(as salt bridge) 10. Two cables with alligator clips 3. Procedure: a. Prepare two beakers that contain copper (II) sulphate 0.5 M and zink sulphate 0.5 M b. A strip of copper and zink are clean with sandpaper c. Roll up a filter paper and wet it with potassium nitrate d. Put copper strip in the copper sulphate solution and zink strip in zink sulphate solution. e. Connect both strip to the voltmeter by using the alligator clips f. Put the filter paper in both beaker then turn on the voltmeter. g. Repeat steps by replace pair of metals below and their suitable solution.

Magnesium Aluminium Zink Ferum Magnesium

Copper Copper Copper Copper Aluminium 4

Aluminium Ferum

Zink Zink

Questions : 1. what is the arrangement of five metals in the series of electrochemistry? 2. what is usage of series of electrochemistry for reaction in chemical cell?

3. what is the properties of elements that can be choosen as the electrode? answer: 1. Mg Al Zn Fe Cu 2. to choose a metals that will be used as the electrodegu 3. metals must be in different positionin the series of

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electrochemistry.

RESULT

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ENHANCE

A car battery is a type of rechargeable battery that supplies electric energy to an automobile. Usually this refers to an SLI battery (starting, lighting, ignition) to power the starter motor, the lights, and the ignition system of a vehicle’s engine. This also may describe a traction battery used for the main power source of an electric vehicle. Automotive starter batteries (usually of lead-acid type) provide a nominal 12-volt potential difference by connecting six galvanic cells in series. Each cell provides 2.1 volts for a total of 12.6 volt at full charge. Lead-acid batteries are made up of plates of lead and separate plates of lead oxide, which are submerged into an electrolyte solution of about 35% sulfuric acid and 65% water. What chemical reaction occur in it?

Answer: The chemical reaction occur are, the electrons is released, allowing them to flow through conductors to produce electricity. As the battery discharges, the acid of the electrolyte reacts with the materials of the plates, changing their surface to lead sulfate. When the battery is recharged, the chemical reaction is reversed: the lead sulfate reforms into lead oxide and lead. With the plates restored to their original condition, the process may now be repeated.

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