Hydrogen
Hydrogen
The lightest alkaline earth metal is Beryllium(Be) having atomic mass 9.012 dalton. The heaviest element in this family is radium.
The lightest and most abundant element in the entire Universe is hydrogen. Hydrogen has an atomic mass of nearly one.
John Dalton was the adept of the atomic theory and a prominent founder.The five main points of John Dalton's atomic theory: · Elements are made of tiny particles called atoms. · All atoms of a given element are identical. · The atoms of a given element are different from those of any other element.
The lightest element of all should have the lightest atomic mass. It is hydrogen-1 isotope. This atom has only one proton and no neutrons.
Hydrogen
The lightest alkaline earth metal is Beryllium(Be) having atomic mass 9.012 dalton. The heaviest element in this family is radium.
Lithium is the lightest metallic element. Its atomic weight is 6.491.
hydrogen
one
Hydrogen
Lithium is the lightest element metal with a relative atomic mass of 7 (3 protons, 4 neutrons).
Hydrogen, at 1.0079
Hydrogen.
hydrogen
Beryllium for it has a Atomic Number of 4.
Technetium which has an atomic mass of 98.