which statement correctly Compares an atom of an Alkali metal with an atom of the alkaline earth metal next to it on the periodic table

Which statement is best described as a atom

Which of these statements explains the difference between nuclear binding energy and the strong nuclear force ?

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.