This introduction covers The Science Behind Solving Crimes within Chromatography for GCSE Chemistry. Revise Chromatography in Chemical Analysis for GCSE Chemistry with 23 exam-style questions and 15 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 1 of 13 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.

🕵️ The Science Behind Solving Crimes

In 1995, a forger was caught because forensic scientists ran chromatography on ink from a document. The ink produced three spots — the forger had mixed different inks to try to match the original. The genuine signature produced only one spot. Paper chromatography, a technique invented in 1944, uses nothing more than paper and solvent to separate mixtures into their individual components. Today it helps catch criminals, test food dyes, and quality-check medicines.

Practice questions for Chromatography

What is the purpose of chromatography?

A. To separate the components of a mixture
B. To measure the mass of a substance
C. To change a substance from a solid to a liquid
D. To make a substance more concentrated

1 markfoundation

Explain how a chromatogram can be used to determine whether a substance is pure or a mixture.

3 marksstandard

Quick recall flashcards

What is chromatography?

A separation technique used to separate mixtures into their individual components based on different affinities for mobile and stationary phases

What does Rf stand for and what does it measure?

Rf = Retention factor. It measures how far a substance travels compared to the solvent (distance moved by substance ÷ distance moved by solvent)

The Science Behind Solving Crimes