Phase Inspection. 1  Framing: proper technique, boring & notching, wood grade, defective or missing members. 2  Window and door installation and water proofing. 3  Exterior sheathing and vapor barrier is correctly installed. â 4 Plumbing and Electrical inside the walls with correct nail stop shield placement.
Hydrogen is the lightest of the elements and is the most abundant element in the universe. (Also reference http://www.ducksters.com/science/chemistry/hydrogen.php) earth's atmosphere
The element hydrogen is a gas, and it is the most abundant element in the universe. Most of the hydrogen on earth is combined with other elements. Hydrogen gas is so light that it easily escapes the earth's gravity at the upper edges of the atmosphere and is lost into outer space.