Answer: Through diffusion
Explanation:
Oxygen can be defined as the most abundant element on earth. It is a gas at room temperature. It becomes the part of the earth crust by the process of diffusion.
Diffusion is a process of movement of molecules from a region of high concentration to the low concentration. The oxygen remains in high concentration in the atmosphere diffuses into earth crust at low concentration.
The units of ppm means parts per million. Also, It is equivalent to milligrams per liter. It is one way of expressing concentration of a substance. It u<span>sually used to describe the concentration of something in water or soil. We calculate the mass of CaCO3 as follows:
Mass = 75 mg/L (.050 L) = <span>3.75 mg CaCO3</span></span>
Hydrogen. It is made up of one electron and one proton.
