If you put a saturated salt solution in a 300ml container, how long before it reaches the desired %RH?

Question

I want to control RH% using MgCl2 (33%RH), NaCl (75% RH), and other different salts. I just dont know how long it takes to reach the desired RH. And how much solution should I add? I have a thermohygrometer but it seems it is not calibrated and i have no means of calibrating the insrument (partly because it is not mine). I dont know if I should wait for more than 6 hours, help please!

Answer 1

Are you sure you are not working on a specific gravity project ? A thermohygrometer is a tool to measure dissolved salts in a solution and does not need calibration. The tool you are using is commonly used with salt water aquarium fish and salt concentrations in the aquarium.