Hypothesis Writing Workshop Notes

Video context and collaborators

• Hypothesis writing workshop video (ENGLISH) developed by the University of Pittsburgh chemistry department in collaboration with Davis and Elkins College.
• First in a series of six videos designed to help students develop and improve scientific writing skills and format lab report sections to resemble research literature.
• Presenter: Grace Murray; paired with an associated video worksheet.
• Workshop produced by Grace Murray, Doctor Michelle Morgan, and Doctor Eugene Wagner (University of Pittsburgh) in collaboration with Clinton Johnson (Davis and Elkins College).
• All student examples have been modified from the Honors General Chemistry Lab at the University of Pittsburgh.

Learning objectives

• Define what a hypothesis is and where it is found in a scientific paper.
• Learn how to write a hypothesis.
• Understand what makes a good hypothesis.
• Note: The video asks learners to pause and complete activities (Activity 1, Activity 2, Activity 3) on a workshop handout before continuing.

Pre-lesson activity

• Pause the video to complete Activity 1 on the hypothesis workshop handout with group participation.
• Return to the video after completing Activity 1.

What is a hypothesis

• A hypothesis is a proposed outcome to demonstrate through experimentation.
• Important limitation: an experiment will never prove a hypothesis; it will either support or reject it.
• Outcome rationale: from the proposed research, you arrive at a conclusion, theory, or understanding that is useful beyond the research itself.
• Location in literature: found after the abstract, normally within the introduction.
• In scientific literature, a hypothesis is rarely stated explicitly; it is often implied and may be expressed as multiple sentences within the introduction that are pieced together.
• The hypothesis should help guide the experiment and the interpretation of results.

Three components of hypotheses in this curriculum

• The three components are: define the unknown, the prediction, and scientific reasoning.

Define (the unknown)

• Purpose: introduce the problem being investigated.
• Length: two sentences max; clearly state the topic and focus of the experiment.
• Form: should not be written as a question; should frame the purpose in direct statements.
• Literature example (defined in the module):
  • "And we might wonder whether this internal complexity can spoil the quantum wave behavior of the center of mass motion. To answer this question, we have set up a new experiment as shown in Figure three. It resembles very much the standard Young's double slit experiment. Like its historical counterpart, our setup also consists of four main parts: the source, the collimation, the diffraction grating, and the detector."
• Important style note: this example is written in the first person in the article; however, published scientific writing should be in the third person.
• The define component also serves to outline how the hypothesis will be tested (i.e., the experimental setup).

Predict (the outcome)

• Purpose: explain what you think will occur as a result of the experiment.
• Characteristics: should be testable and not a numerical prediction (e.g., not a predicted yield or mass).
• Testability depends on the capacity of the lab and equipment; for this curriculum, predictions should align with the scope of the class and lab.
• Literature example (predictions):
  • "Based on these historical achievements, we ask how far we might be able to extend such quantum experiments and for what kind of objects we might still be able to show the wave particle duality."
  • In this example, the subject of the prediction is that fullerene molecules will be used to demonstrate wave-particle duality, thereby fitting the predicted outcome to the study’s focus.
• Takeaway: the prediction should identify the specific areas that will be studied and should be testable with the given methods.

Reasoning (scientific reasoning)

• Purpose: provide scientific evidence that links the prediction to the science being studied.
• Length: one to two sentences.
• Basis: can be grounded in fundamental chemistry principles or scientific literature.
• Literature example (scientific reasoning):
  • "The existence of collective many particle states in fullerene like plasmas and excitons, the rich variety of vibrational and rotational modes, as well as the concept of an internal molecular temperature are only some of the clear indicators of the multiparticle composition of the fullerenes. This, along with the rest of the introduction in this article, are justification for the prediction made. Here, we see that the fullerene molecules are chosen for the multiple states within each single molecule. This makes the comparison between Young's double slit experiment on electrons and the proposed experiment on a large complex molecule like fullerene. It supports the prediction that molecules as large and as complex as fullerene can display particle wave duality."
• Note: the three components can appear in any order in the introduction (the video highlights that define, predict, and reasoning can be presented non-sequentially).

Example of a literature-composed hypothesis (final emphasis)

• The presenter demonstrates that the three components (define, predict, reasoning) can be present in any order in the text.
• Highlighted order in the example: first comes the prediction, next comes the scientific reasoning, and finally the definition of the experiment.
• This serves as a reminder that while a suggested order is useful, real literature may present these components non-linearly.

Student example: aspirin recrystallization (to improve purity)

• The session asks learners to pause and identify where each component is in the student example and to highlight them on the handout.
• Define (aspirin context):
  • Example text: "The process of recrystallization of aspirin is found in large scale production of the drug and often sees multiple rounds of recrystallization to rid the samples of contamination."
  • Follow-up: "Since recrystallization reduces contaminants and leftover reactants in the products, crude aspirin will find more impurities than one round of recrystallization, which will be less pure than pharmaceutical aspirin."
  • Note: the end of the second sentence can be seen as a prediction, but it needs a specific measurable prediction rather than a vague statement.
• Predict (aspirin context):
  • Example text: "The crude sample will react in the iron chloride solution to display a darker color than with the recrystallized aspirin showing the presence of unreacted salicylic acid."
  • Insight: this provides a specific, qualitatively measurable prediction about the iron chloride test and purity.
• Reasoning (aspirin context):
  • Example text: "This contamination can be qualitatively detected using iron chloride. The iron reacts with phenol groups in substances to produce a dark purple brown color. Salicylic acid, a reactant in crude aspirin, has a phenol group while pure aspirin does not."
• Key teaching points from student examples:
  • Example 1: first-person voice and awkwardly introduced hypothesis; too informal.
  • Example 2: first-person voice again; prediction lacks specificity; cannot simply say it will be more pure without a measurable metric.
  • Example 3: lacks a measurable way to determine if it is aspirin per the hypothesis.
  • Example 4: best prediction among the set because it compares purities (though more detail would help, e.g., melting points or IR peaks).
  • Example 5: untestable (no way to determine physiological effect from lab product); still in first person and lacks reasoning.
• Activity 2 and 3 (group work guidance):
  • Activity 2: assess multiple student examples; identify strengths and weaknesses; focus on clear, measurable predictions and third-person writing.
  • Activity 3: create reasoning for a hypothesis from an article about fabric masks; emphasizes 1–2 sentences of reasoning in third person; examples may vary; there is no single correct answer; points to hit include effects of layered fabrics and fabric compositions, and their interaction.

Activity outcomes and rubric

• The workshop ends with a rubric that grades hypotheses across the three components (define, predict, reasoning).
• The rubric contains four grading marks: from below expectations to distinguished.
• Learners should reference the rubric when preparing any hypotheses or writing activities in the curriculum.

Review of key points about hypotheses

• A hypothesis is what you propose to prove via experiments and will be tested during the experiment to reach a conclusion.
• Location: typically found in the introduction (after the abstract); in literature, the hypothesis may be implicit and distributed across sentences.
• The three core components (define, predict, reasoning):
  • Define: introduce the unknown/problem in 2 sentences max, direct statements, not a question.
  • Predict: state what will happen; should be testable; avoid numerical predictions; match lab capabilities.
  • Reasoning: provide 1–2 sentences of scientific justification for the prediction.
• In literature, scientific reasoning is often integrated throughout the introduction rather than isolated to a single sentence.
• Even though the module presents the three components in a specific order (define → predict → reasoning), they may appear in various orders in published work.

Practical and ethical implications in writing hypotheses

• Emphasis on third-person writing for formal scientific communication (avoid first-person phrasing in the published hypothesis).
• Predictions should be precise and measurable to allow objective assessment of outcomes.
• Reasoning should connect the prediction to established scientific principles or literature, providing a defendable basis for the expectation.
• Avoid physiological or ethically problematic predictions (e.g., outcomes that cannot be tested through lab methods or that would involve unsafe assumptions about biological effects).
• The materials emphasize testability and alignment with available instruments and methods in the classroom context.

Final guidance and where to seek help

• If there are questions about the workshop contents, contact the lab instructor.
• The workshop is designed to build toward a full introduction in scientific writing; practice through activities is intended to prepare students for writing a complete introduction in future labs.
• The handout includes a rubric to reference during hypothesis writing and reporting throughout the curriculum.

Credits and attribution

• Created and produced by Grace Murray, Doctor Michelle Morgan, and Doctor Eugene Wagner (University of Pittsburgh).
• Collaboration with Clinton Johnson (Davis and Elkins College).
• All student examples have been modified from the Honors General Chemistry Lab at the University of Pittsburgh.