So are they indeed sp3 hybridized?

I understood all of the examples that you wrote down. But here we have something different. It's a linear molecule and it only forms one bond. Also you gave HCl as an example and it resembles diatomic chlorine. But 100% of the sources say that HCl is unhybridized.

Because user azmanam said in https://www.chemicalforums.com/index.php?topic=37990.0 that it's really not.
He went on to give some bibliography: http://books.google.com/books?id=x6ct1xjyJpoC&pg=PA371&lpg=PA371&dq=vsepr+theory+chlorine&source=bl&ots=uB-xVEvcO3&sig=fvrKp9FyofKCWXYTEMaESxYUYiE&hl=en&ei=p3sWS6HoMtCWlAfHvvzMBQ&sa=X&oi=book_result&ct=result&resnum=3&ved=0CA4Q6AEwAg#v=onepage&q=vsepr%20theory%20chlorine&f=false

If I understood correctly d orbitals don't participate in the bond. So the book that I have at hand must have made a serious mistake

From stack exchange of the chemists: https://chemistry.stackexchange.com/questions/60238/what-is-the-hybridization-of-diatomic-nitrogen-diatomic-anything-like-oyxgen-b a users goes on to say that there is no need for hybridization to occur. I find his explanation very logical.

I know hybridization is just a concept to make sense of nature, but is it really applicable in here? Hybridization is useful whenever multiple bonds are formed, right? Hybridization of diatomic molecules seems quite silly to me. Does it really make sense for hybridization to be present in a single-bonded system?

Thank you for your time!

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.

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?

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.

Hello everyone! It seems nice in here.

I have been searching for a couple of days now and I keep finding unsatisfying information.
My book (not a universally known one) attempts to explain the fact that fluorine forms a weaker halogen elemental bond than chlorine by giving 2 reasons:
1) Closely packed electrons (I guess you have already heard about that)
2) Due to the lack of d orbitals in fluorine. All other halogens have these, which in turn participate in "the hybridization" (?) thus strengthening the halogen-halogen bond.

° So, does it really make sense for Cl₂ to hybridize? Most sources say that hybridization doesn't take place (makes sense right? We are only forming one bond here. Why would we waste so much energy to make all the orbitals degenerate? What are we gaining energetically?).

° How exactly do d orbitals strengthen the bond? Is something like Pi backbonding (as referred to transition metals) taking place here? It makes me very uncomfortable to think about the d orbitals here because everything is so closely packed together (But I guess this logic doesn't apply here. Nitrogen can form a triple bond with ease and a very strong one indeed). Chlorine is not even that big of an atom, do the p-orbitals really share their inert electron pairs with the neighboring halogen's p orbitals?

Thanks for your time, I hope I didn't overlook anything.