Group 1: Reactivity & Electronic Configurations Flashcards

All 4 cards in this deck

In terms of electrons, why are lithium, sodium and potassium placed in group 1, and what ion do they form?

They each have 1 electron in the outer shell, which they lose to form a +1 ion.

Put lithium, sodium and potassium in order of reactivity with water, most reactive first.

Potassium, then sodium, then lithium.
Potassium fizzes most vigorously, moves fastest and burns with a lilac flame; lithium reacts least vigorously.

True or false? Caesium reacts less vigorously with water than potassium.

False. Reactivity increases down group 1, so caesium reacts far more vigorously than potassium — explosively.

Why does reactivity increase going down group 1?

Each element down the group has more shells, so the outer electron is further from the nucleus and more shielded, making it easier to lose.