Give two similarities between be and be2+

They have the same number of protons

They have the same number of neutrons

Explanation:

Considering Be and Be2+, two electrons were lost from the atom for the ion to be formed. The number of protons and the number of neutrons remain the same. Hence the atom and its ion share a similarity in the number of protons and neutrons present in both the atom and ion being exactly the same. This is a similarity between Be2+ and Be- the both possess the same number of neutrons and the both also posses the same number of protons.

i just learnt this recently but i need to look through my notes again

you need to have a picture of the atom that way we can answer it