[Five]

Hi! Im a highschool student looking to make caustic soda at home, as I have heard that all you need to do is electrolyse saltwater to make it and then boil the solution. I have tried this several times with the generic method of a 9v battery and using pencils shaved on both ends as "electrodes" but I couldnt make anything. Recently I have bought two 30cm graphite electrodes, a borosilicate glass beaker and 30 12volt batteries in hopes of doing the experiment properly.

TLDR: I want to make at least a visible amount of NaOH,, how can I do so without getting hurt?

Also, in faradays first law of electrolysis the weight in the formula would be the weight of chlorine and hydrogen gas being deposited on the electrodes,, is this also the weight of NaOH produced?? Thankyou.

[Hunter2]

Read something about chlorine- alkaline electrolysis. There you will find you need a diaphragmatic membrane to separate cathode from anode.

https://www.fuelcellstore.com/image/data/Categories/chlor-alkali-process-schematics.jpg

For the calculation you need the chemical reaction. Develop it.
With Faraday you can calculate the  moles or masses of the developed gases and also with the moles the produced NaOH.

To show in the experiment add some indicator like phenolphthaleine in the cathode compartment . If NaOH is created you see a pink colour around the cathode.

[Five]

Read something about chlorine- alkaline electrolysis. There you will find you need a diaphragmatic membrane to separate cathode from anode.

https://www.fuelcellstore.com/image/data/Categories/chlor-alkali-process-schematics.jpg

For the calculation you need the chemical reaction. Develop it.
With Faraday you can calculate the  moles or masses of the developed gases and also with the moles the produced NaOH.

To show in the experiment add some indicator like phenolphthaleine in the cathode compartment . If NaOH is created you see a pink colour around the cathode.

How do I find the resistance of the mixture?? (since I know the voltage and I need the current for the faraday formula). Do I just dip the probes of my multimeter in it?

The image you provided (thanks) suggests I'd need to provide a constant supply of both brine and water, is that true and if yes how would I do that?

Also what kind of container is best for this,, and where can I get a diaphragmatic membrane?

[Hunter2]

For the conductivity you put a amperemeter in series to the circuit. Don't dip your probes in the solution. Connecting a probe to the plus of the battery then connect the other one via a cable to the  graphite Anode. From cathode you go back to the minus of the battery. Maybe put a switch between to switch on/off.

https://media.sciencephoto.com/image/t3560597/800wm

The resistor is your cell.

The brine, water supply is needed for continously electrolysis. Why? What happen to your solution over time?

Container can be  your beaker in lab. But also a drum .

The membrane are called nafion membrane.

[Five]

For the conductivity you put a amperemeter in series to the circuit. Don't dip your probes in the solution. Connecting a probe to the plus of the battery then connect the other one via a cable to the  graphite Anode. From cathode you go back to the minus of the battery. Maybe put a switch between to switch on/off.

https://media.sciencephoto.com/image/t3560597/800wm

The resistor is your cell.

The brine, water supply is needed for continously electrolysis. Why? What happen to your solution over time?

Container can be a your beaker in lab. But also a drum .

The membrane are called nafion membrane.

Thanks for the help 
I'll make sure to post my results here when I perform the experiment.

[Hunter2]

But do it under a good ventilated hood or outside a building, because you develop poisson chlorine gas.

To be on the safe side use sodium sulfate ( develop oxygen) instead of sodium chloride.