6.5: Quantitative Considerations
- Page ID
- 407712
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An important part of the chapters that follow is a consideration of how we can use the emission or absorbance of photons to determine the concentration of an analyte in a sample. Here we provide a brief summary of quantitative spectroscopic methods of analysis in Table \(\PageIndex{1}\), leaving more specific details for later chapters.
| What happens to the photons? | What do we measure? | What is the relationship between what we measure and concentration, \(C\)? | What are some examples? |
|---|---|---|---|
| emitted | the power, \(P_e\), of emitted light | \(P_e = kC\) | flame atomic emission, molecular fluorescence and phosphorescence |
| scattered | the power, \(P_{sc}\), of scattered light | \(P_{sc} = kC\) | nephelometry, turbidity, Raman spectroscopy |
| absorbed | the power, \(P_t\), of transmitted light relative to the power, \(P_0\), of the light source | \(- \log \left( \frac{P_t}{P_0} \right)\) | flame atomic absorbance, molecular absorbance |