AI - Chemical Industry and Food

Question 1

Give two ways in which chemical production impacts the environment

Answer 1

• Raw materials and sources of energy are taken from the Earth
• Waste products (including those from burning fuel) are released into the environment

Question 2

Give two reasons why less efficient reactions tend to have a greater impact on the environment

Answer 2

• They require more raw materials (including fuel) to make the product
• They produce more waste per unit of product made

Question 3

Define atom economy and give ways in which it can be changed

Answer 3

Atom economy tells you what proportion of the starting materials end up in useful products (e.g. how wasteful the reaction is).
It cannot be changed without changing the reaction

Question 4

Define percentage yield and give ways in which it can be changed

Answer 4

Percentage yield tells you how efficient the entire process is under a particular set of conditions .
It may be changed by carrying out the reaction at a different temperature or pressure

Question 5

Give the equation for % atom economy

Answer 5

% atom economy = (mass of desired product / total mass of all products) x 100

Question 6

Give the equation for % yield

Answer 6

% yield = (actual yield / theoretical yield) x 100

Question 7

Give 4 costs involved in producing a chemical

Answer 7

1) Raw materials
2) Fuel / energy
3) Overhead / fixed costs - e.g. staff wages, taxes, insurance
4) Disposal Cost

Question 8

Give 3 risks involved in producing a chemical

Answer 8

1) Some chemicals (especially gases) are highly flammable and carry a risk of explosion
2) Some chemicals are harmful to health if in contact with them
3) Some chemicals can damage the environment

Question 9

Give 3 ways in which chemicals can improve food production

Answer 9

1) Fertilising the soil
2) Acid neutralisation
3) Killing pests

Question 10

Give 2 reasons why fertiliser must be used in moderation

Answer 10

1) Rain can wash them from soil into the lakes and rivers where they cause excessive algae growth - reducing the amount of light for plants that are needed to oxygenate the water (Eutrophication)
2) Nitrate (V) ions can enter drinking water which poses health risks, especially to young children

Question 11

Give 3 downsides of using pesticides

Answer 11

1) They often end up killing non-pest organisms (some of which can be beneficial to the crop)
2) Some pesticides don’t break down easily, meaning that they can accumulate in the food chain and reach levels harmful to the health of much larger bird and animal species
3) As with fertilisers, they can be washed from the soil and end up in drinking water