A graphic displays elements of the periodic table with the word "ThINK" spelled out using thorium (Th), iodine (I), nitrogen (N), and potassium (K). Each element's atomic number and weight are shown underneath.
A graphic displays elements of the periodic table with the word "ThINK" spelled out using thorium (Th), iodine (I), nitrogen (N), and potassium (K). Each element's atomic number and weight are shown underneath.