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Galvanic cell prac obsolete? (1 Viewer)

.ben

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hi can someone tell me why the syllabus has these two dotpts:

 Perform a first-hand investigation to identify the conditions under which a galvanic cell is produced

 Perform a first-hand investigation and gather first-hand information to measure the difference in potential of different combinations of metals in an electrolyte solution

They seem so pointless as they are covered in teh previous dotpoints. what do we have to write for these two?

thanks
 

Riviet

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The first dotpoint is asking for you to identify what conditions are needed for the galvanic cell to properly operate, such as the two half cells being physically separated, the use of a salt bridge, the anode/cathode electrodes being used, etc.

For the second, the dotpoint is asking for you to have tried different combinations of metals when connected to the galvanic cell and observed how they have affected the potential difference produced.
 
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.ben

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Ok thanks for that. so you can roll both into one experiment?
 

funking_you

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.ben said:
hi can someone tell me why the syllabus has these two dotpts:

 Perform a first-hand investigation to identify the conditions under which a galvanic cell is produced

 Perform a first-hand investigation and gather first-hand information to measure the difference in potential of different combinations of metals in an electrolyte solution

They seem so pointless as they are covered in teh previous dotpoints. what do we have to write for these two?

thanks
The CONDITIONS for setting galvanic cell would be:

* concentration =1 mol/L
* temperature = 25oC
also, although not soo important
* pressure = 1 atm (101.3 kPa)

The voltages given on the HSC data sheet are VALID for these conditions. Changing these conditions of the experiment will change the voltage.


The first dotpoint is asking for you to identify what conditions are needed for the galvanic cell to properly operate, such as the two half cells being physically separated, the use of a salt bridge, the anode/cathode electrodes being used, etc.
These are not related to the conditions under which a galvanic cell will operate.
You do not need to physically seperate the halfcells, you set up a galvanic cell in one container, which would mean you do not need a salt bridge in some cases.

You need to remember that a galvanic cell is defined as any spontaneous electrochemical cell that converts stored chemical energy into electrical energy.
Thats is what a galvanic cell is,

too many students think a galvanic cell IS the experimental setup consisting of two beakers with salt bridge etc...
that is just ONE way of setting up a galvanic cell, which is used heaps in the HSC cause its the best at illustrating how a galvanic cell works.


Cheers,
George
 

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