The diagram shows a portion of the periodic table. Elements that were unknown during Mendeleevs time have been removed. Using Mendeleevs rules for arranging elements, which box would contain the metal gallium, which has an atomic number of 31 and an atomic mass of 70?

To prevent the presence of air, noble gases are placed over highly reactive chemicals to act as inert "blanketing" gases. a chemical engineer places a mixture of noble gases consisting of 4.37 g of he, 13.36 g of ne, and 36.65 g of kr in a piston-cylinder assembly at stp. calculate the partial pressure in torr of kr.