Why nonpolar solvent "picks up" water?

[Hyo X]

Most solvents we use in the laboratory have some shelf life. Experimental example: Say you have a 4L bottle of anhydrous toluene and you regularly pour out/use small volumes of it over the course of a year. One year from opening date, you have 1L of toluene left.
Will this toluene still be "anhydrous" or will it have some small amount of water picked up from humidity in the atmosphere? Isn't toluene immiscible with water? So why would water solvate into a nonpolar solvent like this? is there a way to calculate/estimate the quality of the solvent after some time?

 

[Bystander]

Will this toluene still be "anhydrous" or will it have some small amount of water picked up from humidity in the atmosphere? Isn't toluene immiscible with water? So why would water solvate into a nonpolar solvent like this? is there a way to calculate/estimate the quality of the solvent after some time?

No, and yes. No. Everything is soluble to some degree in everything else. No.

 

[rbelli1]

When you transfer the solvent from one vessel to another you are not just pouring the solvent. You are also pouring atmosphere into the source vessel. It is a matter of perspective.

Try to pour hydrogen from one vessel to another in normal atmosphere. You need to have the destination vessel "upside down."

BoB

PS: see you can make a similar video with everything inverted with hydrogen.