7.1 - Green Chemistry

Question 1

What are bulk chemicals?

Answer 1

Chemicals that are produced on a large scale in very large quantities.

Question 2

What are 4 examples of bulk chemicals?

Answer 2

1. Ammonia
2. Sulfuric acid
3. Sodium Hydroxide
4. Phosphoric Acid

Question 3

What are fine chemicals?

Answer 3

Chemicals that are produced on a small scale in much smaller quantities.

Question 4

What are 3 examples of fine chemicals?

Answer 4

1. Drugs
2. Food additives
3. Fragrances

Question 5

What are 2 issues with Chemical Research?

Answer 5

1. Time-consuming (takes years)

2. Really expensive

Question 6

What is ensured that chemicals are protected from the people and the environment?

Answer 6

Governments place strict controls and regulations on everything to do with chemical processes.

Question 7

What are the 3 types of chemical regulations?

Answer 7

1. Using chemicals
2. Storage
3. Transport

Question 8

What are the 5 stages of chemical production?

Answer 8

1. Preparation of feedstock (the actual reactants)
2. Synthesis (converting the reactants to products)
3. Separation of products (i.e. useful and waste)
4. Monitoring the purity of the product
5. Handling of by-products and wastes

Question 9

What are the 8 KEY questions when considering sustainability?

Answer 9

1. Will the RAW MATERIALS run out?
2. How good is the ATOM ECONOMY?
3. What do I do with the WASTE PRODUCTS?
4. What are the ENERGY COSTS?
5. Will it damage the ENVIRONMENT?
6. What are the HEALTH AND SAFETY risks?
7. Are there any BENEFITS/RISKS to SOCIETY?
8. Is it PROFITABLE?

Question 10

During a chemical reaction, what happens?

Answer 10

Old bonds are broken. New bonds are formed.

Question 11

Energy must be _____ to _____ existing bonds. This is called an _________ process.

Answer 11

Energy must be SUPPLIED to BREAK existing bonds. This is called an ENDOTHERMIC process.

Question 12

Energy is ________ when ___ bonds are _____. This is called an __________ process.

Answer 12

Energy is RELEASED when NEW bonds are FORMED. This is called an EXOTHERMIC process.

Question 13

If more energy is given out than taken in, what is the overall result of a reaction?

Answer 13

The reaction is EXOTHERMIC.

Question 14

If more energy is taken in than given out, what is the overall result of a reaction?

Answer 14

The reaction is ENDOTHERMIC.

Question 15

What are the 5 steps when working out Bond Energy calculations?

Answer 15

1. Take a look at the reaction given and separate them into reactants and products.
2. Calculate the energy required to break the original bonds (given in the question).
3. Calculate the energy released by forming the new bonds (given in the question).
4. Use the formula OVERALL ENERGY CHANGE = ENERGY REQUIRED - ENERGY RELEASED to work out the overall energy change.
5. If the answer is a negative number, it’s exothermic. If positive, endothermic.

Question 16

How can Energy Changes be visualised?

Answer 16

Using an Energy Level Diagram.

Question 17

In exothermic reactions, what is shown on an Energy Level Diagram?

Answer 17

Reactants are higher than products.

Question 18

In endothermic reactions, what is shown on an Energy Level Diagram?

Answer 18

Reactants are lower than products.

Question 19

What is the ‘Activation Energy’?

Answer 19

The minimum amount of energy needed to start a reaction.

Question 20

How is the ‘Activation Energy’ shown on an Energy Level diagram?

Answer 20

It’s the peak of the curve.

Question 21

What do catalysts do in terms of the Activation Energy?

Answer 21

Catalysts LOWER the activation energy needed for reactions to happen (by providing alternative routes).

Question 22

If the Activation Energy is high, what does that mean?

Answer 22

Very few molecules may have enough activation energy to start reacting.

Question 23

If the Activation Energy is low, what does that mean?

Answer 23

Many more molecules may have enough activation energy to start reacting.

Question 24

What do some industrial processes do to speed up the rate of reaction?

Answer 24

They use enzyme catalysts.

Question 25

What could happen if the conditions for enzyme catalysts are not controlled well?

Answer 25

The enzymes can DENATURE and their shape changes due to the change in conditions. That means they can never work.

Question 26

How would you work out the Relative Atomic Mass (RAM) of an element?

Answer 26

Take a look at the Periodic table. Usually, the larger number is the RAM. Most tables position above the symbol.

Question 27

How would you work out the Relative Formula Mass (RFM) of a molecule/compound?

Answer 27

Adding together the Relative Atomic Masses of every atom in the formula.

Question 28

How would you work out the actual masses of reactants and products?

Answer 28

1. Work out the RAM/RFM of each reactant or product involved in the question (make sure equation is balanced)
2. Link the values together in a ratio.
3. Scale down to 1g.
4. Scale up to the values in the question