Reactivity Trends: Group 2

Question 1

How many outer electrons does each group 2 element have?

Answer 1

Two.

Question 2

What is the most common reaction for group 2 elements and describe the reaction.

Answer 2

The most common reaction is a redox reaction where each metal atom is oxidised, losing two electrons to form a 2+ ion with the electron configuration of a noble gas.

Question 3

Because the group 2 element has been oxidised what type of agent is it?

Answer 3

Reducing agent.

Question 4

What happens when a group 2 element reacts with oxygen? Write the general word equation.

Answer 4

They form a metal oxide.

Metal + Oxygen = Metal Oxide

Question 5

What happens when a group 2 element reacts with water? Write the general word equation.

Answer 5

They form an alkaline hydroxide and hydrogen gas.

Metal + Water = Alkaline Hydroxide and Hydrogen

Question 6

What happens when a group 2 element reacts with dilute acids? Write the general word equation.

Answer 6

They form a salt and hydrogen.

Metal + Acid = Salt and Hydrogen

Question 7

Describe and explain what happens to first ionisation energy down group 2.

Answer 7

Decreased nuclear attraction,
Increased atomic radius,
Increased shielding,
Ionisation energy decreases.

Question 8

What happens when a group 2 oxide reacts with water? Write the general word equation.

Answer 8

Release hydroxide ions forming alkaline solutions.

Metal oxide + Water = Metal ion + Hydroxide ions

Metal ion + hydroxide ions = Metal Hydroxide

Question 9

Describe the solubility, pH and alkalinity trend for the metal hydroxides down group 2.

Answer 9

Solubility increases,
pH increases,
Alkalinity increases.