does sodium hydroxide expire/lose potency?

[Dreamwalker]

So the other day I was in a discount store and in the plumbing section I came across a few bottles of Glug drain opener. I purchased a bottle and checked out the spec info online and I'm sure its 100% sodium hydroxide chips. The only thing I'm concerned about is these bottles look pretty old. On the website for the company it even states that its an old product that they no longer make it. From just looking at it Im guessing its at least 10 years old or more.

Anybody know if its still good? Does this stuff ever expire or lose any potency over time? Just wondering before I go buy the rest of them if its even worth it.
Thanks in advance!

 

[tryptographer]

If the container is closed well and the chips are dry, chances are not too bad.

NaOH is so hygroscopic it dissolves in the water it attracts from the air. It also vigorously sucks CO2 from the air, forming sodium carbonate. A small pile of NaOH left in the open will convert to sodium carbonate in a matter of days! But in a good container it can keep well for years.

You could throw some of it in dilute HCl; if there are gas bubbles there is carbonate present. Even if that's the case, it may well be worthwhile - good luck!

 

[Dreamwalker]

Cool thanks. I guess I'll test it out and see what happens. I wasn't even looking for this stuff I just happened to come across it randomly in a discount shop. There really aren't any stores around here that sell it and I don't like buying it online. I was surprised not only to find it but to find it so cheap also. There was a seal under the cap so I'm guessing its good. I guess I'll find out when I test it!!