How To Unclog A Bathroom Sink With Baking Soda And Vinegar. Fill a measuring cup with 1/3 cup baking soda and 1/3 cup vinegar. It should then start to bubble.
This is an old method for unclogging drains that work well in bathroom sinks. If the drain begins to drain, continue to flush with hot tap water. Pour 1 cup of baking soda and a mixture of 1 cup vinegar and 1 cup water down the sink drain.