Patients who waited more than 6 months to receive cataract surgery experienced more vision loss, a reduced quality of life and had an increased rate of falls compared with patients who had wait times of less than 6 weeks.
Group 16 is the oxygen family. It consists of the elements oxygen, sulfur, selenium, tellurium, and polonium. Each has six of the desired eight electrons required for the octet in its highest energy level.
The group numbers on the periodic table reference electron configurations. Elements in group 17 or group VIIA (same group), they will have 7 valence electrons. The row or period an element is found on references the highest occupied energy level for that element.