active transport requires the usage of energy in the form of ATP to  move something against is concentration gradient. Facilitated  diffusion is a form of simple diffusion i â¦ n that the substance moves  along with its concentration gradient, but it requires the use of a  transport protein.
Quick Answer. The atomic mass of the element neon is 20.18 amu, or atomic mass units. This number, which appears on the periodic table underneath the chemical symbol for neon, Ne, represents the weighted average of the isotopic masses of neon's isotopes based on their abundance in nature. Continue Reading.
The atomic mass for an atom of hydrogen is one dalton, which is calculated from the lone proton. Remember, electrons are too small to be considered in the atomic mass. Helium is the second lightest element, and is larger than hydrogen. It consists of two protons and two neutrons. Because protons and neutrons are approximately the same size, the atomic mass of a helium atom is four daltons. Let's look at a larger atom. Barium has an atomic mass of 137 daltons.