Periodicity

Question 1

What is First Ionisation Energy?

Answer 1

The energy required to remove 1 mol of electrons from 1 mole of gaseous atoms

Question 2

As you go along period 2 how does the bonding change?

Answer 2

Metallic bonding, Giant covalent bonding, Simple covalent bonding

Question 3

Trend in boiling points across period 2?

Answer 3

Increasing to Carbon, Decreasing past carbon

Question 4

What is a Redox Reaction?

Answer 4

A reaction where one reactant is oxidised and another is reduced

Question 5

What are the redox reactions of group 2?

Answer 5

magnesium with hot water: gas evolves
magnesium with dilute acid: fizzing, magnesium disappearing
magnesium with steam: emits lots of light and heat, gas evolves

calcium with cold water: fizzing, solution goes cloudy
calcium with hot water: fizzing, solution goes cloudy
calcium with dilute acid: solid disappearing, fizzing

Question 6

What are the reactions of group 2 compounds?

Answer 6

magnesium oxide with water: solid dissolves, water turns cloudy, alkaline
calcium oxide with water: fizzing, solid disappears, water turns cloudy, more alkaline than magnesium

Question 7

What are the uses of group 2 compounds?

Answer 7

Oxides: Reducing soil acidity, by increasing soil pH.
Carbonates and Hydroxides: Indigestion aids

Question 8

What colours do halgens have when dissolved into water?

Answer 8

Chlorine - pale green
Bromine - yellow/orange
Idodine - brown

Question 9

Disproportionation reactions of chlorine?

Answer 9

Cl2 + H2O -> HCl + HClO
NaOH + Cl2 -> NaClO + HCl

Question 10

What is the ion test for carbonate ions?

Answer 10

add acid to solution, if a gas evolves test gas by bubbling in limewater, if limewater turns cloudy you have carbonate ions in the solution

Question 11

What is the ion test for sulphate ions?

Answer 11

add acid to solution, add a barrium salt such as barium chloride to the solution, if a white precipitate forms, there is sulphate ions in the solution

Question 12

What is the ion test for nitrate ions?

Answer 12

add aluminium powder to solution and sodium hydroxide, heat the solution and hold damp red litmus paper above the heated solution
If the damp red litmus paper turns blue there are nitrate ions in the solution

Question 13

What is the ion test for ammonium ions?

Answer 13

add sodium hydroide to the solution and heat, hold damp red litmus paper above the heated solution
If the damp red litmus paper turns blue you have ammonium ions in the solution

Question 14

What is the test for halide ions?

Answer 14

add acid to the solution and silver nitrate, if there are halide ions present a precipitate will form.
Chloride: White
Bromide: Cream
Iodide: Yellow

To better tell them appart, you can try redissolve the silver halid in ammonia solution.
Chloride: dissolves in dilute ammonia solution
Bromide: dissolves in concentrated ammonia solution
Iodide: doesn’t redissolve