Which correctly summarizes the trend in electron affinity?
it tends to be very high for group 2.
it tends to be more negative across a period.
it tends to remain the same across periods.
it tends to be more negative down a group.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.