I bought a huge jar back in 2020 that is 2 lbs in weight. It's not quite 3 years old, but I wonder how far down I would have to go to make sure it's as pure as possible. It doesn't have a paper seal under the plastic cap, but it's in a plastic jar that is stored inside of a plastic bag, so maybe it's okay. I also bought some new SN this year, so it's probably a lot more potent but, I'm curious to know if the old stuff is any good.
Was it from fishing store? I have one too but there were a few reports that people were getting nitrate instead of nitrite. I saw this review on it on Amazon titled "Packaging Issue" and don't know if it has to do with seller selling nitrate or what person had went bad over time:
" I thought this would last a long time but my nitrite is mostly nitrate at this point. Even with the lid on tight and properly stored. Now I need to get a new shipment:( "
I am bad at math, let alone know nothing about chemistry. I wanted to ask about aquarium testing method with aquarium strips on chemistry forum and folks did not understand what I want from them. I wanted to understand why that method would be a good indicator and know how changing certain parameters would affect the accuracy. I asked why it has to be 1000ml of water, why 5g of chemical because some guides instruct to use 1g of chemical. Why mix 5g in 10ml of water and not 100ml of water before I add it to 990ml/900ml water bottle.
They asked what I want tested "quantity" or "quality" of the chemical. Quality is that purity thing mentioned on the packaging and quantity is PPM or mg /L. And since aquarium testing strips test PPM the target amount i.e. 10 is an indication of a very low amount of chemical in the water. If my SN is 100% pure I would see 10 PPM on a testing strip. If claimed purity was 90% I would see 9 PPM and if claimed purity was 50% I would see 5 PPM on a testing strip? If the target result is 10 PPM why instructions mention to make 5g of SN solution and not 10g? I saw even guide where 1g was mentioned.