March 11, 2026

IB Chemistry: How to Write a Perfect IA Evaluation (Step-by-Step)

The evaluation is one of the highest-scoring sections of the Chemistry IA — yet most students write it in a rushed paragraph.

🧪 1. Identify 3–4 Major Weaknesses

Examiners don't want:

❌ "Human error occurred."

❌ "We could have used more accurate tools."

They want:

✔️ Specific

✔️ Scientific

✔️ Measurable weaknesses

Examples:

Reaction mixture not fully sealed → gas loss
Colour change judged by eye → subjective error
Temperature fluctuations → kinetic changes

🛠 2. Propose Real Improvements

Each weakness must have a realistic improvement.

❌ "Use better equipment."

✔️ "Replace manual titration with an automatic titrator to reduce end-point variability."

📉 3. Show How It Affects Accuracy or Reliability

For each weakness → explain:

How it affected results
Whether it caused systematic or random error
How your improvement fixes it

This is where marks jump.

📊 4. End With a Judgement

One sentence:

"The reliability of the conclusion is limited due to the experimental weaknesses identified, particularly X and Y."

Clear. Mature. Examiner-friendly.

📲 Get Chemistry IA templates & examples in StudyIB

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