Oxygen And Oxides

Question 0

Composition of air

Answer 0

Nitrogen- 78
Oxygen- 21
Carbon dioxide- 0.03
Other (eg argon)- 1

Question 1

Percentage volume of oxygen experiments

Answer 1

Experiment with copper
Experiment with iron
Experiment with phosphorus

Question 3

Experiment with copper for oxygen

Answer 3

Fill gas syringe with air (100cm^3)
Push through a silica tube containing copper powder
The oxygen reacts with the copper powder and the gas in the second is measured

Question 4

Experiment with iron for oxygen

Answer 4

Iron wool is placed in a test tube
Test tube inverted in a beaker of water
Test tube is filled with air and left for a few days
Length of the column of air is measured before and after
It decreases

Question 5

Experiment with phosphorus for oxygen

Answer 5

Marked bell jar with no bung is placed on top of coins inside a trough
Water is poured into trough until is reached level zero
Phosphorus is placed on an evaporating dish which floats on water
Phosphorus is lit
Lid/bung is put on bell jar
Phosphorus burns and air space fills with white fumes
This phosphorus oxide
This dissolves in water to form an acidic solutions
When phosphorus stops burning water is higher inside the bell jar than outside

Question 5

Oxygen and magnesium

Answer 5

White bright light, forming a white solid called magnesium oxide

Question 6

Preparation of oxygen

Answer 6

Hydrogen peroxide spontaneously decomposes into water and oxygen
Manganese oxide is the catalyst

Question 7

Oxygen and carbon

Answer 7

Colourless and an odourless gas produced

Question 8

Equation for magnesium and oxygen

Answer 8

2Mg(s)+O2 –> 2MgO

Question 9

Oxygen and sulphur

Answer 9

Pungent yellowish gas produced

Question 10

Equation for carbon and oxygen

Answer 10

C+O2 –> CO2

Question 11

Carbon dioxide preparation and specific equation

Answer 11

Metal carbonate + acid

Thermal decomposition of a metal carbonate

Question 12

Equation for sulphur and oxygen

Answer 12

S+O2 –> SO2

Question 13

Metal carbonate and acid for oxygen equation

Answer 13

CaCO3(s) + 2HCl(aq) –> CaCl2(aq) + 2H2O + CO2

Question 14

CO2 preparation with carbonate

Answer 14

CaCO3 (s) + 2HCl (aq) –> CaCl (aq) + H2O (l) + CO2 (g)

Question 15

CO2 preparation with thermal decomposition

Answer 15

Copper carbonate green to black
Magnesium carbonate stays white
Calcium carbonate stays white
Zinc carbonate white to yellow to white

Question 17

CO2 properties

Answer 17

Not very soluble in water
More soluble under pressure
Denser than air

Question 18

CO2 drinks

Answer 18

When put under pressure its soluble in drinks to make fizzy drinks

Question 18

Acid rain problems

Answer 18

Corrosive (erodes buildings)
Leaches minerals out of soil
Fish cant survive

Question 19

CO2 fire extinguishers

Answer 19

Denser than air
Sits on burning fuel
Prevents oxygen reaching it

Question 21

Magnesium and hydrochloric or sulphuric acid

Answer 21

Bubbles of gas
Magnesium disappears
Reactions gets hot
Colourless solution formed

Question 22

Aluminium and hydrochloric or sulphuric acid

Answer 22

Slow when cold but bubbles when rates
Aluminium disappears
Colourless solution formed

Question 22

Iron and hydrochloric or sulphuric acid

Answer 22

Bubbles if gas
Iron disappears
Pale green solution formed

Question 23

Zinc and hydrochloric or sulphuric acid

Answer 23

Bubbles if gas
Zinc disappears
Colourless solution formed

Question 25

Combustion of hydrogen equation

Answer 25

2H2(g) + O2(g) –> 2H2O (l)

Question 26

Test for water

Answer 26

Ass anhydrous copper sulphate
White powder turns blue
Forms hydrated copper sulfate
CuSO4 + 5H2O –> CuSO4 5H2O