How Significant Figures Are Handled in Stemble

How Significant Figures Are Interpreted

Stemble evaluates the number you enter exactly as written. Unlike a human grader, the system cannot infer your intended level of precision from context.

This means that:

• Digits you include are treated as significant

• Digits you omit are treated as not significant

• Trailing zeros are interpreted based on how the number is written, not how you meant it

If the system reports an issue with significant figures, it is responding to the format of your answer, not judging your understanding of the chemistry.

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Trailing Zeros and What They Mean

Trailing zeros are one of the most common sources of confusion.

In chemistry (and most sciences), a human grader may interpret the number 500 based on context. A computer cannot.

Here’s how Stemble interprets different ways of writing the same value:

• 500 → ambiguous precision

• 5e2 → one significant figure

• 5.00e2 → three significant figures

If precision matters, scientific notation is the most reliable way to communicate it unambiguously.

For example:

• If your answer is one significant figure, write 5e2

• If your answer is three significant figures, write 5.00e2

Writing 500 alone does not reliably communicate either case.

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Using Scientific Notation to Show Precision

Scientific notation allows you to explicitly control the number of significant figures in your answer.

If you are unsure how to enter scientific notation correctly, see: How to Enter Scientific Notation in Stemble

Using scientific notation is often the safest choice when trailing zeros are involved.

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Significant Figures in Multi-Part Questions

Significant figure issues often appear in multi-part questions, especially when later parts depend on earlier calculations.

A common failure mode looks like this:

• You calculate an intermediate value

• You round it and submit that rounded value

• You re-enter the rounded value in a later step

• Rounding error accumulates and affects the final result

Even if each individual step seems reasonable, early rounding can push later answers outside the accepted range.

To avoid this:

• Keep full precision in your calculator for intermediate steps

• Only round when asked for a final answer

• Avoid retyping rounded intermediate values into later parts of a question

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Why a Correct Calculation Can Still Be Marked Incorrect

If your math is correct but your answer is marked incorrect, common reasons include:

• An incorrect number of significant figures

• Ambiguous trailing zeros

• Rounding too early in a multi-step calculation

• Entering a rounded intermediate value instead of the full-precision result

In most cases, this reflects a precision or formatting issue, not a misunderstanding of the chemistry.

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What to Do If You’re Unsure About Significant Figures

If you’re unsure how many significant figures are expected:

• Check the question instructions carefully

• Review course-specific guidance from your instructor

If you believe the issue is related to how your answer was interpreted:

• Review this article and the scientific notation guide

• Contact support with your course name, assignment name, and task number

Grading expectations and tolerances are set by your instructor, so conceptual questions about significant figures should be directed to them.