Color, phase, odor and boiling point are the physical properties. Reactivity with oxygen depends on the chemical nature of object, thus, it is not a physical property. It is a chemical property.
Rocks are minerals, made up of many minerals. There are 3 types of rocks which are Igneous, Sedementary, and Metamorphic.
Hey there! :D
To some extent, all moving parts produce friction. It can be very small or minimal, but all parts produce some form of friction.
This is true.
I hope this helps!
~kaikers
it means two oxygen atoms