To unclog a bathroom sink with standing water, first, remove as much water as you can. Pour half a cup of baking soda into the drain, followed by half a cup of vinegar. Cover the drain and let the mixture sit and fizz for about 30 minutes to break down the clog. Afterward, flush the drain with boiling water to clear any remaining debris. If needed, use a plunger to create suction and further dislodge the clog.
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