Question

14. What does the “lock and key” design in some pharmaceutical drugs refer to?
A drug molecule that binds to a pathogen to transport it out of the body
The shape of the pathogen that fits into the body’s cells
The reaction of a drug with other molecules in the body to form new compounds
A process used to create new materials for the chemical industry

15. What is a major disadvantage of using plastics in products?
Plastics are naturally found in the environment
Plastics cannot be molded into different shapes
Plastics are not biodegradable and contribute to long-term environmental pollution
Plastics are highly conductive and dangerous to handle

16. What is a key step in designing a successful chemical system?
Ignoring environmental impacts to focus on efficiency
Focusing only on the technical aspects of the system
Identifying criteria and constraints
Ensuring that the system is as complex as possible

17. When designing a chemical system, what should be minimized?
Cost of materials
Environmental impacts
Efficiency of the system
Time to design

18. What is the purpose of sedimentation in a water purification system?
To remove small, dissolved particles from the water
To filter the water through a semipermeable membrane
To soften hard water
To allow sediments to settle at the bottom and be removed

19. Why might a community include an ion exchange system in its water purification system?
To increase the water’s hardness
To filter out large particles from the water
To remove calcium and magnesium ions, softening the water
To increase the concentration of sodium in the water

20. Who can be particularly negatively affected by ion exchange water purification systems?
People with high blood pressure and/or kidney disease who need to avoid sodium
People with low blood pressure and/or kidney disease who need to avoid sodium
People with low blood pressure and/or kidney disease who need to avoid magnesium and calcium

21. What is the role of a semipermeable membrane in water purification systems?
To allow only specific materials to pass through based on size or chemical properties
To allow all materials to pass through freely
To completely filter out all substances from the solution
To increase the temperature of the water

22. Why is photosynthesis considered a chemical system?
It involves chemical reactions where reactants are converted into products
It produces waste products that can be used in other systems
It uses energy only in the form of heat
It only involves biological components

23. What is pomace, and why has it only recently been used extensively?
Pomace is the edible part of fruits, and it has been used for centuries in cooking
Pomace is a chemical compound, and its use has increased due to its strong antioxidant properties
Pomace is a byproduct of water purification, and it is used to clean water
Pomace is the pulp that remains after juices are removed, and its use has increased due to advances in extraction technologies

24. Why is it desirable to use pomace for many purposes?
Pomace is highly toxic and must be disposed of carefully
It is a waste product, and reusing it reduces environmental pollution

Answer 1

14. A drug molecule that binds to a pathogen to transport it out of the body (closest match — lock-and-key refers to a drug designed to fit a biological target/receptor)
15. Plastics are not biodegradable and contribute to long-term environmental pollution
16. Identifying criteria and constraints
17. Environmental impacts
18. To allow sediments to settle at the bottom and be removed
19. To remove calcium and magnesium ions, softening the water
20. People with high blood pressure and/or kidney disease who need to avoid sodium
21. To allow only specific materials to pass through based on size or chemical properties
22. It involves chemical reactions where reactants are converted into products
23. Pomace is the pulp that remains after juices are removed, and its use has increased due to advances in extraction technologies
24. It is a waste product, and reusing it reduces environmental pollution