Scientists use the periodic table to quickly refer to information about an element, like atomic mass and chemical symbol. The periodic table’s arrangement also allows scientists to discern trends in ...

was less than the atomic mass (average mass of the atom). For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass ...

Accompanying Lesson Plan: Lesson 3.2: Finding Volume—The Water Displacement Method The chart shows that atomic size and mass for the ... Polyethylene is made up only of carbon and hydrogen atoms. The ...

Its two sources of fuel, hydrogen and lithium, are widely available in many ... Fission splits a heavy element (with a high atomic mass number) into fragments; while fusion joins two light elements ...