A plastic bottle partially filled with water floats on water, even though the density of the plastic (1.2 g/cc) is more than that of water. Why is that?

True the plastic will float because of the principle of flotation or buoyancy

Explanation:

Buoyancy explains it all!!

Buoyancy  is the upward force/upthrust experienced by a body immersed totally or partially in a liquid.

According to the principle of flotation:

"when a body is totally or partially immersed in liquid it experiences an upthrust which is equal to the volume of fluid displaced"

The plastic will float due to the fact the average density of the total volume of the plastic and the air inside it is less than the same volume of water it is floating in

good looking response

answer: good job it's all correct !

explanation: