Question Focus: The diagram shows an early stage where a plant material is processed and something is separated out. We need to identify what is separated from the raw material.
Correct Answer: D
Passage Reference: The process for making Nature Works PLA begins when a renewable resource such as corn is milled, separating starch from the raw material.
Why this is correct: The diagram is showing the milling stage. The passage clearly says the resource is milled, separating starch from the raw material. So the correct label here is starch.
Common Mistake: Some students choose dextrose because it appears soon after. But dextrose is made later from starch, not separated at this stage. This is a sequence trap.
Paraphrasing: Passage: 'separating starch from the raw material' = Diagram: '___ is separated from the raw material'
Tips: When a diagram shows the first steps, match it to the earliest process sentence in the passage.
Key Vocabulary:
- milled = ground into smaller pieces
- raw material = basic natural material
Question Focus: The diagram shows the step where dextrose is changed into lactic acid. We need the name of this process.
Correct Answer: F
Passage Reference: Cargill Dow turns the unrefined dextrose into lactic acid using a fermentation process similar to that used by beer and wine producers.
Why this is correct: The diagram shows dextrose being transformed into lactic acid. The passage says this happens using a fermentation process. So the correct answer is fermentation.
Common Mistake: A common wrong choice is condensation because it sounds technical. But condensation happens later, after lactic acid is formed. This is a wrong section trap.
Paraphrasing: Passage: 'turns the unrefined dextrose into lactic acid using a fermentation process' = Diagram: 'dextrose is changed by ___'
Tips: If the diagram shows a change from one substance to another, look for verbs like turn into or change into in the passage.
Key Vocabulary:
- fermentation = chemical change using natural processes
- unrefined = not fully cleaned or purified
Question Focus: The diagram shows what happens after lactic acid is produced and before purification. We need the process name.
Correct Answer: B
Passage Reference: Through a special condensation process, a lactide is formed.
Why this is correct: After lactic acid is made, the passage says through a special condensation process, a lactide is formed. That matches this diagram step exactly, so the answer is condensation.
Common Mistake: Some students choose distillation because purification is mentioned nearby. But distillation happens after condensation, not before. This is a sequence trap.
Paraphrasing: Passage: 'Through a special condensation process, a lactide is formed' = Diagram: 'lactic acid is processed by ___'
Tips: Always check what comes before and after a step. Diagrams usually follow the same order as the passage.
Key Vocabulary:
- condensation = process of combining substances
- formed = created
Question Focus: The diagram shows the final product that is ready for use. We need to label what the purified material becomes.
Correct Answer: H
Passage Reference: This lactide is purified through vacuum distillation and becomes a polymer (the base for NatureWorks PLA that is ready for use through a solvent-free melt process.
Why this is correct: At the final stage, the passage explains that the purified lactide becomes a polymer and is ready for use. That matches the last box in the diagram, so the answer is polymer.
Common Mistake: Students sometimes pick distillation because purification is mentioned. But the diagram asks for the result, not the method. This is a context shift trap.
Paraphrasing: Passage: 'becomes a polymer that is ready for use' = Diagram: 'final product: ___'
Tips: For the last box in a process diagram, look for phrases like final, ready for use, or becomes.
Key Vocabulary:
- polymer = large material made of many small units
- purified = cleaned
General Tips:
- Diagram questions usually follow the passage order. Use the previous answer to help you find the next one.
- Focus on what the diagram box is asking for. Is it a material or a process?
- Do not choose a word just because it sounds scientific. Check the exact stage carefully.
- Cross out options as you use them so you do not reuse the same word.
