3.1.2 Group 2: Module 3: Periodic Table and Energy: Chemistry OCR A A Level

What is a common name given to group 2 metals?

Alkaline Earth Metals

What is the most reactive metal of group 2?

Barium

List 3 physical properties of group 2 metals

● High melting and boiling points.

● Low density metals.

● Form colourless (white) compounds.

The highest energy electrons of group 2 metals are in which subshell?

S subshell

Does reactivity increase or decrease down group 2? Why?

● Increases.

● Electrons are lost more easily because larger

atomic radius and more shielding.

What happens to the first ionisation energy as you go down group 2? Why?

Decreases because:

● Number of filled electron shells increases down the group → increased shielding.

● Increased atomic radius → weaker force between outer .

● Electron and nucleus → less energy needed to remove electron.

What type of reaction is the reaction between group 2 elements and oxygen?

Redox Reaction

What are the products when group 2 elements react with water?

Hydroxide and hydrogen gas.

Which group 2 element doesn’t react with water?

Beryllium

Which group 2 element reacts

very slowly with water?

Magnesium

What type of reaction is the reaction between group 2 metal and water?

Redox Reaction

What is oxidised and what is reduced in a reaction between group 2 metal and water?

Metal → oxidised

One hydrogen atom from each water → reduced

What are the products when a group 2 element reacts with an dilute acid?

Salt and hydrogen gas.

Write an equation for the reaction of calcium and hydrochloric acid.

Ca(s) + 2HCl(aq) → CaCl2(s) + H₂(g)

What is formed when group 2 oxides react with water?

Metal Hydroxide

Write an equation for the reaction between a group 2 oxide and water.

MO(s) + H2O(l) → M(OH)2(aq)

What group 2 metal oxide is insoluble in water?

Beryllium Oxide

What is the trend in hydroxide solubility down group 2?

● Increases down the group

● Mg(OH)₂ is slightly soluble

● Ba(OH)₂ creates a strong alkaline solution

What is Ca(OH)2 used for? Write an equation related to one of its uses.

Used to neutralise soil:

Ca(OH)₂ (aq) + 2HCl (aq) → 2H₂O (l) + CaCl₂ (aq)

What is Mg(OH) 2 used for?

Milk of magnesia - antacid to treat indigestion, heartburn, etc.

What is calcium carbonate used for?

Present in limestone and marble. Used in building construction.