Non-Metals & Their Compounds - Unit 2 Topic 8

Question 1

What are the physical properties of hydrogen?

Answer 1

Colourless, odourless gas, lighter than air, insoluble in air + burns explosively in air.

Question 2

What are the 2 equations if hydrogen reacts with:

• Oxygen
• CuO

Answer 2

2H2 + O2 -> 2H2O

H2 + CuO -> Cu + H2O

Question 3

What general equation do we use to prepare hydrogen?

Answer 3

Metal + acid -> salt + hydrogen

Question 4

What is a clean fuel?

Answer 4

Fuel which when burned doesn’t produce any toxic or polluting products.

Question 5

What are the benefits of using hydrogen as a fuel?

Answer 5

Clean fuel + can be used safely in fuel cells.

Question 6

What are the drawbacks of using hydrogen as a fuel?

Answer 6

Must be manufactured as not naturally abundant, fuel cells expensive, very flammable and leaks hard to detect, storage tanks must be well insulated to prevent liquid H2 turning to gas and escaping.

Question 7

Give 3 uses for hydrogen?

Answer 7

Clean fuel, rocket engines + meteorological balloons.

Question 8

What are 3 uses of carbon dioxide?

Answer 8

Fire extinguisher, carbonated drinks + dry ice.

Question 9

What are the physical properties of carbon dioxide?

Answer 9

Colourless, odourless gas, heavier than air, slightly soluble in water, doesn’t support combustion + acidic.

Question 10

What is the test for carbon dioxide? (Equation)

What if there is excess CO2?

Answer 10

Bubbled through limewater, turns milky-cloudy.
CO2 + Ca(OH)2 -> CaCO3 + H2O
Turns back to colourless
CO2 + CaCO3 + H2O -> Ca(HCO3)2

Question 11

What do you notice at the rim of a bottle of sodium hydroxide?

Answer 11

White crust.

Question 12

Give 3 observations when CaCO3 reacts with HCl

Answer 12

Disappears, fizzing, exothermic.

Question 13

What is the formula for carbonic acid?

Answer 13

H2CO3

Question 14

What happens when a piece of burning Mg is put into a jar of CO2?

Answer 14

Continues to burn with bright white light, black soot forms + white ash forms.

Question 15

What are the physical properties of nitrogen?

Answer 15

Colourless, odourless, same weight as air, insoluble in water + doesn’t burn.

Question 16

What are 2 uses of nitrogen?

Answer 16

Coolant + food packaging.

Question 17

What are the physical properties of oxygen?

Answer 17

Gas, colourless, odourless, same weight as air + supports combustion.

Question 18

What are 3 uses for oxygen?

Answer 18

Medicine, welding + rocket engines.

Question 19

What is the test for oxygen?

Answer 19

Relights a glowing splint.

Question 20

How do we collect oxygen when we make a sample?

Answer 20

Over water as it’s only slightly soluble in water.

Question 21

What is the definition of combustion?

Answer 21

Fuel reacting with oxygen to produce oxides and energy.

Question 22

What are the physical properties of ammonia?

Answer 22

Colourless gas, characteristic smell, lighter than air, very soluble in water + produces an alkaline solution.

Question 23

How is ammonia collected?

Answer 23

Ammonia Fountain Experiment. Water injected into flask which dissolves ammonia and pressure increases which draws up water from trough.

Question 24

What are the advantages of nitrogenous fertilisers?

Answer 24

Greater nitrogen uptake by plant which makes them larger + healthier.
Increases crop yield + profit.

Question 25

What are the disadvantages of nitrogenous fertilisers?

Answer 25

If fertiliser gets into rivers, eutrophication. | In drinking water causes stomach cancer + gives babies blue baby syndrome.

Question 26

What can aqueous ammonia be used for?

Answer 26

Testing for the presence of metal ions in solutions.

Question 27

``` Aqueous ammonia precipitate colours: Mg2+ Cu2+ Al3+ Fe2+ Fe3+ Zn2+ ```

Answer 27

``` White Pale blue White Green Red-brown White ```

Question 28

``` Aqueous ammonia excess NaOH solubility: Mg2+ Cu2+ Al3+ Fe2+ Fe3+ Zn2+ ```

Answer 28

``` No Yes dark blue solution No No No Yes colourless solution ```

Question 29

What process is used to make ammonia? What reactants, temperature, pressure + catalyst? What percentage of gases react to form ammonia? Is it reversible?

Answer 29

The haber process Nitrogen + hydrogen, 450c, 200atm, Iron. 20%. Yes.

Question 30

The highest % yield of ammonia is produced in ultra high pressure, why is this not used?

Answer 30

Very expensive and dangerous.

Question 31

The % yield of ammonia is increased at low temp, why isn't this used?

Answer 31

Catalyst won't work below 450c.

Question 32

What colour is sulfur? What flame colour is sulfur? What are the 3 allotropes of sulfur?

Answer 32

Yellow solid Blue flame Rhombic sulfur, monoclinic sulfur + plastic sulfur.

Question 33

What is an allotrope?

Answer 33

Different forms of the same element in the same physical state.

Question 34

What are the physical properties of sulfur dioxide?

Answer 34

Yellow, pungent gas. Heavier than air, soluble in water + forms acidic solution.

Question 35

What is sulfur present in?

Answer 35

Fossil fuels

Question 36

What effect does acid rain have when it falls on a forest?

Answer 36

Difficulty in photosynthesising as leaf damaged + leaches nutrients from soil.

Question 37

What effect does acid rain have when it falls on rivers, lakes + streams?

Answer 37

Water becomes acidic which kills fish. Acidic water absorbs poisonous metal ions like aluminium which also kill fish.

Question 38

What effect does acid rain have when it falls on limestone rocks, buildings + pavements?

Answer 38

Reacts with calcium carbonate in limestone so it corrodes.

Question 39

What measures are used for prevent acid rain + how do they work?

Answer 39

Burn less fossil fuel - electricity used efficiently + renewable resources used. Remove sulfur from fossil fuels - petrol + diesel. Remove acidic gases from combustion products - scrubbers on chimney stacks which neutralise gases before they escape.

Question 40

What process is used for making sulfuric acid? | What are the 4 main stages?

Answer 40

The Contact Process Combustion of sulfur to form SO2, catalytic production of sulfur trioxide by mixing SO2 with more air to produce SO3. Absorption in concentrated sulphuric acid by dissolving SO3 in H2SO4 to form oleum H2S2O7. Oleum mixed with water to produce concentrated sulphuric acid to form 2H2SO4.

Question 41

``` The Contact Process: Temp Pressure Catalyst Why can't sulfur trioxide be added directly to water? ```

Answer 41

450c 2atm Vanadium Oxide (V2O5) Too exothermic, acidic mist formed which is difficult to contain.

Question 42

What does sulfuric acid act as when it is concentrated?

Answer 42

Dehydrating agent,

Question 43

What happens when sulfuric acid is reacted with sugar + equation?

Answer 43

Dehydrate/remove water from sugar leaving carbon. C6H12O6 -> 6H2O + 6C Darkens, sugar turns black, black column rises from beaker with steam, exothermic, burnt caramel smell.

Question 44

What happens when sulfuric acid is reacted with hydrated CuSO4 + equation?

Answer 44

Removes water of crystallisation from blue crystals leaving white anhydrous copper sulfate + blue solution formed. CuSO4.5H2O -> CuSO4 + 5H2O

Question 45

Should you add acid to water or add water to acid?

Answer 45

Add acid to water.

Question 46

What happens when sulfuric acid is reacted with calcium carbonate? What if it was copper carbonate?

Answer 46

White solid disappears, colourless gas bubbles + heat. | Green powder disappears, colourless gas bubbles + heat.