IB Chemistry SL Internal Assessment Example

You situate the investigation in a specific and relevant chemical and pharmaceutical context.

You show strong understanding of the ethanoic acid/ethanoate equilibrium and use it to justify the variable you chose.

Your procedure is mostly detailed and reproducible, with controlled variables and a clear sequence of steps.

The context would be stronger if it more clearly separated buffer behavior from the endpoint-based quantity actually measured.

The method does not fully match the stated aim of measuring true buffer capacity.

Some procedural details are still ambiguous, especially the exact equipment and the missing standardization result for NaOH.

Your raw data and processed tables are well organized and easy to follow.

You present the experimental trend clearly, and your graph communicates the relationship between the variables effectively.

You do consider uncertainty through repeats, apparatus uncertainties, and propagated error estimates.

The main calculation does not correctly represent true buffer capacity, because it uses a fixed endpoint rather than a differential pH-based measure.

Several important uncertainties are omitted or not fully propagated, especially the standardized NaOH concentration and buffer preparation.

The treatment of pH uncertainty is not fully appropriate for the way the calculation is written.