Trends in the periodic table indicate that the element with the greatest ionization energy is in which of the following periods and groups? a
Period 2, Group 1
b
Period 7, Group 2
c
Period 6, Group 17
d
Period 1, Group 18

D Period 1, Group 18

Explanation:

it's helium

it's top right corner of the periodic table

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.