The Periodic Table

Question 1

When you go down Group 1, why does reactivity increase?

Answer 1

The atoms in Group 1 want to lose an electron to become ions.
As you go down the group, the size of the atoms increases; this means that the electrostatic attraction that the outside electron feels becomes weaker as you go down the group.
If the electrostatic attraction is weaker, it is easier to lose that electron.

Question 2

When you go down Group 7, why does reactivity decrease?

Answer 2

The atoms in Group 7 want to gain an electron to become ions.
As you go down the group, the size of the atoms increases; this means that the electrostatic attraction that the outside electrons feel becomes weaker as you go down the group.
If the electrostatic attraction is weaker, it is harder to gain and maintain an electron.

Question 3

What is activation energy?

Answer 3

The energy required for a reaction to take place.

Question 4

How can the rate of reaction be increased?

Answer 4

• Increasing temperature
• Increasing pressure
• Increasing concentration
• Increasing surface area: volume ratio

Question 5

Which reactions have higher activation energy: exothermic or endothermic?

Answer 5

Endothermic.