I NEED HELP PLEASE, THANKS! :)

What do elements in a group on the periodic table have in common?

They have the same number of neutrons in the nucleus.
They have similar chemical properties.
They have the same atomic mass.
Their valence electrons have the same energy level.

Elements in the same group in a periodic table have similar chemical properties.

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.