Which element belongs in Group I?
Sodium
Oxygen
Iodine
The Periodic Table arranges elements in order of increasing...
Mass Number
Reactivity
Atomic Number
The Noble Gases are unreactive because they have full outer shells.
Groups arrange elements according to the number of energy levels.
Why are group I elements called 'alkali metals'?
Because they have pH numbers of 7.
Because they react wth water to produce a metal hydroxide.
Because they become increasingly reactive and violent as you go down the group.
