Elements that lie in the same column on the periodic table (called a group) have identical valance electron configurations and consequently behave in a similar fashion chemically. For instance, all the group 18 elements are inert, or noble gases. Element groups are either nonmetals or various subsets of metals, but there is no distinct line between the two types of elements. Metal elements are usually good conductors of both electricity and heat. Subsets are based on similar characteristics and chemical properties.
3 doctors agreed: A few hours: The typical dilating drops used at most eye doctors last about 4-6 hours. Some individuals are more sensitive to the effects and can remain dilated for up to a day. And if stronger dilating drops were used for a particular reason, their effects could last from 8 to 24 hours. ...Read more.
What Are Dilating Eye Drops? Sep. Your pupils are the round, black openings at the center of your iris (the colored part of your eye). Your iris opens and closes the pupil to allow more or less light into the eye. For your eye doctor to look inside your eyes, your pupils must be dilated (widened). Dilating eye drops enlarge your pupils and keep them from getting smaller when the doctor shines light in your eyes. Next What to Expect When Your Eyes Are Dilated. Related What to Expect When Your Eyes Are Dilated.