Topic 4

What is the trend in ionisation energy down group 2

Decreases down the group

Why does the ionisation energy follow that pattern down group 2

Each following element has another shell which shields the outer electrons

Why is the reactivity like that down group 2

There is less attraction between the outer electrons and the nucleus

How do elements Mg and Ba react with oxygen

Form oxides

How do the elements Mg and Ba react with chlorine

Form chlorides

How do the elements Mg and Ba react with water

Form metal hydroxides and hydrogen

How do the oxides of group 2 react with water

Form metal hydroxides which dissolve

How do the oxides of group 2 react with dilute acid

Neutralise, forming solutions of the corresponding salts

How do the hydroxides of group 2 react with dilute acid

Neutralise, forming solutions of the corresponding salts

What is the trend in solubility of group 2 hydroxides

Increase solubility down the group

What is the trend in solubility of group 2 sulphates

Decrease solubility down the group

What is the trend in thermal stability of nitrates of group 1

Decompose to nitrites and oxygen (excluding LiNO3)

What is the trend in thermal stability of nitrates of group 2

Decompose to form oxide, nitrogen dioxide and oxygen

What is the trend in thermal stability of carbonates of group 1

Thermally stable (except from Li2CO3)

What is the trend in thermal stability of carbonates of group 2

Decompose to form oxide and carbon dioxide

Flame colour for lithium

red

Flame colour for sodium

yellow

Flame colour for potassium

lilac

Flame colour for rubidium

red

Flame colour for caesium

blue

Flame colour of magnesium

none

Flame colour of calcium

brick-red

Flame colour of Strontium

crimson

Flame colour of barium

green

Why do the melting and boiling points of group 7 behave how they do

Increase down the group, increase in electron shells so London forces get stronger

What physical states are group 7 elements in at room temp

Fluorine & Chlorine - Gas

Bromine - Liquid

Iodine - Solid

What is the pattern to electronegativity in group 7

Increases up the group

Why does the reactivity of group 7 follow the pattern it does

Less reactive down the group - Atoms become larger so outer electrons are further away from nucleus, and more shielded

How can you test for carbonate and hydrogencarbonate ions

When HCl added fizzing

CO2 turns limewater cloudy

How can you test for sulphate ions

Acidified barium chloride

How to test for ammonium ions

Damp litmus paper or NaOH