Help How long is sn effective in water

[Acritarch]

I would like to prepare my SN 1-2 hours in advance.
Is it still effective if I dissolve the SN in water and leave it in a sealable bottle?

Maybe if I add propranolol would anything change?

 

[tary]

Suicide Wiki ( https://web.archive.org/web/20210912075803/https://suicide.wiki/index.php?title=Sodium_Nitrite ) says:

"The water solution is potent for few hours."

So I think that two hours or even one could already significantly affect the effectiveness.