Atomic Structure

Question 1

What are isotopes?

Answer 1

Atoms with the same number of protons but different number of neutrons.

Question 2

What is an allotrope?

Answer 2

different forms of the same element in the same physical state
the atoms are bonded differently.
Carbon has allotropes: - Diamond. - Graphite.

Question 3

Why does the reactivity of group 1 increase as you go down the group?

Answer 3

The reactivity of group 1 elements increases as you go down the group because the atoms become larger, which means that the outer electron becomes further from the nucleus.
This in turn means that the electrostatic attraction between the positive nucleus and the outer negative electron decreases in strength.
As a result the outer electron will be lost more easily, and so the element will be more reactive.