1 Consider the first atom of each part of the molecule. An atom with higher atomic number has higher priority. (e.g. I > Cl > C > H)  If the first atom of two groups is the same, consider the second atom(s) in the same way as the first. (e.g. -C(CH3)3 > -CH(CH3)2 > -CH2CH3 > -CH3).
1 You can also use a toilet plunger on your bathroom sink. 2  Fill up the sink with water first, the use the plunger vigorously on the drain just as you would a toilet. 3  This will lift and agitate any blockage in the drain. It will smell a bit like vinegar for about a day. 2  You can also use a toilet plunger on your bathroom sink. 3  Fill up the sink with water first, the use the plunger vigorously on the drain just as you would a toilet.
Pop-Up Type Bathtub Drain. Probably the worst type of drain for catching hair is the pop-up style of drain stopper. There is nothing to stop the hair from leaving the tub and getting into the drain and there is lots of stuff in the drain for it to catch on. The first thing to do is grab hold of the pop-up stopper and lift it out of the drain. It is hinged and bends at the hinges to allow removal and reinsertion into the drain.