shit to remember

Question 1

Electrolysis of water

Answer 1

Cathode: 2H+ +2e- –> H2 (reduced)
Anode: 2O2- –> O2 + 2e- (oxidised)

ions= H+ and OH-

Question 2

Electrolysis of aluminium

Answer 2

Cathode: Al3 + 3e- –> Al (reduction)
Anode: 2O2 –> O2 + 4e- (oxidised)

ions= Al3+ and O2-

Question 3

Thermite reaction (making iron)

Answer 3

Iron Oxide + Aluminium –> Iron + Aluminium Oxide
Fe2O3 + Al –> Fe + Al2O3

OR

2Al + Fe2O3 –> 2Fe + Al2O3

Question 4

Moles

Answer 4

• Moles= concentration x volume / 1000

(divide by a thousand to convert to dm3)

• Moles= mass / Mr

Question 5

The Haber process (ammonia)

Answer 5

Nitrogen + Hydrogen Ammonia

N2 + 3H2 2NH3(g)

Question 6

The Contact process (sulfuric acid)

Answer 6

2SO2 + O2 2SO3

Question 7

What is the catalyst in the Haber process (ammonia)

Answer 7

Iron (Fe)

Question 8

What is the catalyst in the Contact process (sulfuric acid)

Answer 8

Vanadium (V)

Question 9

Yield using moles

Answer 9

1. mass of known / Mr of known x Mr unknown = theoretic yield
2. mass i have for real / theoretical yield x 100 = % yield

Question 10

Concentration (using moles)

Answer 10

conc= moles x 1000 / volume

Question 11

The reactivity series

Answer 11

Potassium 
Sodium 
Calcium 
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Hydrogen
Copper
Silver
Gold
(Please Stop Calling Me A Crazy Zebra Instead Try Learning How Copper Silver Gold)

Question 12

Combustion

Answer 12

Fuel + Oxygen –> CO2 + Water

(C+H) + O2 H2O

Question 13

What is the fire triangle made up of and how do you stop each one?

Answer 13

Oxygen- fire blanket/foam
Heat- water
Fuel- cut down vegetation

Question 14

What happens at the negative electrode?

Answer 14

Cathode (cations)
Positively charged ions gain electrons (reduction)
eg- Pb2+ + 2e- –> Pb

Question 15

What happens at the positive electrode?

Answer 15

Anode (anions)
Negatively charged ions loose electrons (oxidation)
eg- 2Br- –> Br2 + 2e-

Question 16

What is an ore

Answer 16

a substance found in the Earth’s crust, containing metal atoms combined with other elements. They are extracted through chemical reactions (displaced) or through electrolysis

Question 17

What does iron ore do in extracting iron process?

Answer 17

Iron (III) oxide or Fe2O3 is a compound that the iron is extracted from

Question 18

What does coke do in extracting iron process?

Answer 18

Carbon (C) is used as a fuel and reacts to form carbon monoxide to reduce Iron (III) oxide quicker

Question 19

What does limestone do in extracting iron process?

Answer 19

Limestone (CaCO3) removes impurities from the iron by reacting with them to form molten slag

Question 20

What does air do in extracting iron process?

Answer 20

Oxygen (O2) allows the coke to burn, and also produces heat