I unclogged my bathroom sink in under 5 minutes with no chemicals. My sink would drain very slow due to it was clogged. The pipe trap was blocked or clogged with hair and other stuff. I used an ordinary garden hose to fix/unclog my drain in a few minutes.
I had to find a way to fix my sink without using chemicals because I have bad allergies. I have been using this technique for years without any problems.
Remove the stopper by taking out the pivot arm and then snap it back into place.
Blast water down drain pipe and remove anything that is clogging your sink.
Put stopper back and reattach pivot arm and you’re done.