Which element has the same number of valence electrons as bromine (Br)?

(1 point)
Responses

selenium (Se)
selenium (Se)

chlorine (Cl)
chlorine (Cl)

potassium (K)
potassium (K)

krypton (Kr)

3 answers

chlorine (Cl)
Why are sodium (Na) and potassium (K) in the same group on the periodic table?(1 point)
Responses

They have similar reactivity.
They have similar reactivity.

They have similar atomic weights.
They have similar atomic weights.

They are both hard and brittle.
They are both hard and brittle.

They are both colorless.
They have similar reactivity.