Your question is hard to answer for you have not made it clear what you are asking. The term "is less dense than?" is not a question. If you were to ask "What is less dense than snow or water?" That would be a correct question.
no
Gases are less dense than solids.
A wooden block can be less dense than water.
Ice is less dense than water
Ammonia is less dense than air at room temperature and pressure. This is why ammonia gas rises in air.
Water is less dense than any of the other materials listed.In order of density from least to highest:Water (least dense)GraniteBasaltIron (most dense)
Oil IS already less dense than water.
Yes, saliva is less dense than oil. Saliva is composed primarily of water, whereas oil is made up of non-polar molecules that are less dense than water.
Ice is a solid less dense than the liquid
Chlorine gas is less dense than water, so it will float on top of water if the two are in contact.
No, the only planet in the solar system less dense than water is Saturn.
Easy, put a fruit in water and if it floats it is less dense than water.