Practical Task (1 Viewer)

[ChelseaMiller]

Hi all


I have a prac assessment coming up and I need help with a few experiments with method and calculations (these are the main ones for now). The pracs are: Galvanic cell, energy content of fuels and acids and bases/pH/concentration (the teacher said it could be any pH pracs we did). On top of that is a titration but I certain I can do that, so it's just the three experiments.


Thanks for any responses

 

[golgo13]

What ur asking is somewhat unclear but i'll try to answer it
For galvanic cells, the general gist of the prac requires a voltmeter (or Multimeter), generally you will pick metals such as (copper, iron, zinc, magnesium) with the corresponding Sulphate or nitrate solutions (copper sulphate, etc etc). You will need a slat bridge which is a piece of filter paper dipped in potasium nitrate. To do calculations you have the E0 values behind periodic table should be given if not you can grab off BOS

The second prac you describe sounds like a molar heat of combustion one, Basically you will get a spirit burner,Where you weight it with the alcohol (ethanol etc) and you try to raise the temperature of water by a fixed amount say 2 degrees. You will then need to reweigh it calculate mass difference and work out for the molar heat of combustion with the change in temperature and how much energy it gives. Not much just apply the formula

Titration is just titration pick and appropriate indicator so that you get and appropriate endpoint

I'm also thinking you will need to assess why you didn't get the theoretical values that shouldn't be hard textbook should cover that

I hope that helps

 

[VJ30]

Galvanic cell involves the concept of oxidation and reduction. You have to pick two electrodes (eg Zinc and Copper) and their corresponding salts (zinc sulfate and copper sulfate). You also need nacl for salt bridge and a voltmeter. Remember:

OIL- oxidation is loss of electrons

RED CAT- reduction happens at cathode

In ph-concentration- they will give u a concentration and u have to work its pH or vice versa..HCL is common simple example. But beware of Sulfuric acid as it is diprotic so you have to double its concentration and also Triprotic ones and know about strong and weak acids and bases
All the best.

 

[ChelseaMiller]

What ur asking is somewhat unclear

Sorry but that's all I was given too

 

[ChelseaMiller]

Did my prac and it ended up being the galvanic cell one. Found it really easy which made me think if I had missed something really important :/

 

[Kimyia]

OILRIG: oxidation is loss, reduction is gain
AN OX: oxidation occurs at the anode
RED CAT: reduction occurs at the cathode.

 

[VJ30]

OILRIG: oxidation is loss, reduction is gain
AN OX: oxidation occurs at the anode
RED CAT: reduction occurs at the cathode.

if u memorise OIL then theres no need to remember RIG, and if you remember REDCAT then theres no need to remember AN OX...isnt it??

 

[kdizzler]

Roman Catholic Adults Only
Reduction: Cathode
Oxidation: Anode