Definitions
Example Sentences
"The atomic number 21 corresponds to the element scandium in the periodic table."
"Scandium's atomic number 21 indicates the number of protons in its nucleus."
"At room temperature and pressure, the atomic number 21 element is a silvery-white metal."
"The position of scandium with atomic number 21 in the periodic table is between calcium and titanium."
"Isotopes of the atomic number 21 element have different numbers of neutrons."
