Harbor Process And Organic Chemistry

Question 1

What happens if a reversible reaction takes place in a closed system*?

Answer 1

The reaction will reach a state of equilibrium which means the amounts of reactants and products will reach a certain balance and stay there.
(A closed system means the substances can’t escape)

Question 2

What directions do the reactions go in a reversible reaction?

Answer 2

The reactions take place in both directions but the overall effect is nil because the forward and reverse reactions cancel each other out.

Question 3

At what rate do the reactions take place in, in a reversible reaction?

Answer 3

The reactions take place at exactly the same rate in both directions.

Question 4

In a reversible reaction what does the position of equilibrium depend on?

Answer 4

The temperature and pressure surround the reaction.

Question 5

What happens when you alter the temperature/pressure of a reversible reaction?

Answer 5

You can move the position of equilibrium to give more product and less reactants.

Question 6

What happens if you raise the temperature in a reversible reaction?

Answer 6

The endothermic reaction will increase to use up the extra heat.

Question 7

What happens if you decrease the temperature in a reversible reaction?

Answer 7

The exothermic reaction will increase to give out more heat.

Question 8

How is volume distributed in a reversible reaction?

Answer 8

Many reactions have a greater volume on one side, either of products or reactants.
(A greater volume means there are more gas molecules)

Question 9

How does raising the pressure effect an reversible reaction?

Answer 9

It encourages the reaction which produces less volume.

Question 10

How does lowering the pressure effect an reversible reaction?

Answer 10

It will encourage the reaction which produces more volume.

Question 11

How does a catalyst effect a reversible reaction?

Answer 11

The catalyst speeds up both the forward and backward reactions by the same amount.
So the reaction will reach equilibrium quicker.

Question 12

What reacts to form ammonia?

Answer 12

Nitrogen and hydrogen.

Question 13

How are the products for ammonia productions obtained?

Answer 13

Nitrogen is obtained easily from the air.

Hydrogen comes from natural gas or other sources like crude oil.

Question 14

What time of reaction is nitrogen and hydrogen?

Answer 14

Some of the nitrogen and hydrogen reacts to form ammonia but as it is reversible ammonia breaks down back into nitrogen and hydrogen.

Question 15

What are the optimum industrial conditions for the haber process?

Answer 15

Pressure = 200 atmospheres
Temperature = 450 degrees
Catalyst = iron

Question 16

What compromises are made for te conditions in the haber process?

Answer 16

The pressure is set as high as possible to give the best % yield without making the plant to expensive so it is set at 200 atmos.
The yield of ammonia would be greater at lower temperatures however this means a lower reaction rate so they increase the reaction anyway to get a faster rate of reaction.

Question 17

Why do higher pressures favour the forward reaction in the haber process?

Answer 17

Since there are four molecules of gas on the left side(greater volume) for every two on the right(less volume) meaning the reaction will go forward.

Question 18

Why would the yield of ammonia be greater at lower temperatures?

Answer 18

As the forward reaction is exothermic, which means the increasing temperature will move the equilibrium the wrong way (away from ammonia towards H2 and N2)

Question 19

Why is the iron catalyst important in the haber process?

Answer 19

Without the catalyst the temperature would have to be raised even further to get a quick enough reaction and that would reduce the % yield even further.

Question 20

What is a reversible reaction?

Answer 20

A reaction where the products of the reaction can themselves react to produce the original reactions.

Question 21

What is the general formula of an alcohol?

Answer 21

C(n)H(2n+1)OH

Question 22

What is the functional group of an alcohol?

Answer 22

C-OH

Question 23

What is the homologous series?

Answer 23

A group of chemicals that react in a similar way because they have the same functional group.

Question 24

What are the first three alcohols?

Answer 24

Methanol (1 carbon)
Ethanol (2 carbon)
Propanol (3 carbon)

Question 25

What are the properties of the first three alcohols?

Answer 25

Alcohols are flammable, they burn in air to produce carbon dioxide and water.
They all dissolve completely in water to form neutral solutions.
They also react with sodium to give hydrogen and alkoxides.

Question 26

Why are alcohols useful solvents?

Answer 26

Alcohols can dissolve substances water can’t such as hydrocarbons, oils and fats.

Question 27

What is methylated spirit?

Answer 27

Ethanol with chemicals added to it.

It’s used to clean paint brushes and as a fuel.

Question 28

What is the functional group of a carboxylic acid?

Answer 28

-COOH

Question 29

What is the naming system for alcohols?

Answer 29

Replace the last ‘e’ with ‘ol’

Question 30

What is the naming system for carboxylic acids?

Answer 30

Start with ‘meth/eth/prop’ and end in ‘-anoic acid’.

Question 31

What happens when carboxylic acids react with carbonates?

Answer 31

They react with carbonates to produce carbon dioxide.

The salts formed in these reactions end in ‘-anoate’.

Question 32

What happens when carboxylic acids dissolve in water?

Answer 32

They dissolve in water to produce acidic solutions.

When they dissolve they ionise and release H+ ions which are responsible for making the solution acidic.

Question 33

Why do carboxylic acids produce weak acidic solutions?

Answer 33

When they dissolve in water they ionise and release H+ ions but they don’t ionise completely (meaning not many H+ ions are released).
This means they have a higher pH so less acidic than other solutions of strong acids.

Question 34

What is the difference between strength and concentration of an acid?

Answer 34

Concentration is how watered down your acid is.

Strength is how well it had ionised in water.

Question 35

What can carboxylic acids be used for in industry?

Answer 35

Carboxylic acids with longer chains of carbon atoms are used to make soaps and detergents.
Carboxylic acids are also used in the preparation of esters.
Ethanoic acid is used as a solvent for many organic molecules.

Question 36

What is the equation to form an ester?

Answer 36

alcohol + carboxylic acid ➡➡➡ ester +water

Question 37

What is the naming system for esters?

Answer 37

Their names end in ‘-oate’
The alcohol forms the first part of the esters name and the acid forms the second part.
E.g. Methanol + propanic acid➡
Methyl propanoate + water

Question 38

What are the problems with esters?

Answer 38

Inhaling the fumes from some esters irritates mucous membranes in the nose and mouth.
Ester fumes are heavier than flames and very flammable.
Some esters are toxic, especially in large doses.

Question 39

What are the advantages of esters?

Answer 39

They smell nice so can be used in perfumes.
Also used to make flavourings and aromas.
Some esters can be used as solvents for paint, ink, glue and are less toxic and volatile than other organic solvents.