Q8P Bone consists of the protein col... [FREE SOLUTION]

Chapter 21: Q8P (page 556)

Bone consists of the protein collagen and the mineral hydroxyapatite, ${Ca}_{10} ({PO}_{4})_{6} (OH)_{2}$ . The content of archaeological human skeletons measured by graphite furnace atomic absorption sheds light on customs and economic status of individuals in historical times. $^{37}$ Explain why ${La}^{3 +}$ is added to bone samples to suppress matrix interference in Pbanalysis.

Short Answer

Expert verified

${La}^{3 +}$ appears to be a releasing agent, as it preferentially reacts with ${PO}_{4}^{2 -}$ , releasing ${Pb}^{2 +}$ .

Step by step solution

Define the release agent.

A release agent (also known as a release coating, release agent, or mould release coating) is a substance that prevents other materials from adhering to surfaces. Mould release, die-cast release, plastic release, adhesive release, tyre and web release are all procedures where it can help.

Explain why La3+ is added to bone samples to suppress matrix interference in Pb analysis.

To avoid the chemical matrix effect, ${La}^{3 +}$ is employed. By creating thermally stable compounds, ${PO}_{4}^{2 -}$ prevents the atomization of ${Pb}^{2 +}$ . ${La}^{3 +}$ appears to be a releasing agent, as it preferentially reacts with ${PO}_{4}^{2 -}$ , releasing ${Pb}^{2 +}$ .