What chemical doesn't sink when placed into water?

Asked to answer. Firstly, I'm assuming you're at STP. Many things. Aayush Gehlot is absolutely right. Almost any gas will work. Even ridiculously dense gases, like Tellurium hexafluoride which about 11 times denser than air, are still far, far less dense than water. read more

Lots of chemicals don't sink when placed into water. Some chemicals, such as table salt (NaCl), dissolve into the water, although a large chunk of it will sink before dissolving. read more

Chemicals will enter into tap water from many different types of sources. Pollution is one way that chemicals have gotten into the tap water supplies. Other ways are when chemicals are added to the water by the public water systems. read more