All of these are compounds except oxygen because a compound is two or more different elements bonded together.
Quantitative observations include numerical data. Ex: 32 degrees, 10 inches, etc.
Answer:
Light travels in a straight line until it strikes an object.
As white light passes through a prism , it bends and separates into different colors
D as the two substances could have close boiling points, so if the temperature is not controlled well, both substances will evaporate.
breaking bonds in reactants and forming new bonds in products. Breaking bonds requires energy, and forming bonds releases energy.