Remove the cover and boil another kettle of water. Pour the boiling water down the drain slowly. This washes away the loosened debris and the baking soda-vinegar residue.
This method works best for caused by grease, soap scum, food particles, and hair. It may not work for completely blocked drains (where water stands still for hours). how to unclog sink using baking soda
As soon as you pour the vinegar, you will hear a distinct fizzing and bubbling sound. This is the chemical reaction—carbon dioxide gas—working to agitate the clog and push debris down the pipe. Remove the cover and boil another kettle of water