Question 23 – Nitrogen compounds, polymers and synthesis - Questions

This question is about $α\alpha$ -amino acids with the general formula $RCH(NH2)COOH\text{RCH}(\text{NH}_2)\text{COOH}$ .

Table 1 shows the R groups of four different amino acids.

Table 1

To identify an unknown sample which is one of the four amino acids listed in Table 1, a student performs a titration:

The student weighs out $g3.93\text{ g}$ of the amino acid sample, dissolves it in deionised water, and makes the solution up to exactly $cm3250.0\text{ cm}^3$ in a volumetric flask.
A $cm325.0\text{ cm}^3$ sample of $dm−30.150\text{ mol dm}^{-3}$ hydrochloric acid is pipetted into a conical flask.
The amino acid solution is titrated from a burette into the conical flask.
The average titre of the amino acid solution required to reach the end-point is $cm331.25\text{ cm}^3$ .

This question is about $α\alpha$ -amino acids with the general formula $RCH(NH2)COOH\text{RCH}(\text{NH}_2)\text{COOH}$ .

Table 1 shows the R groups of four different amino acids.

Table 1

To identify an unknown sample which is one of the four amino acids listed in Table 1, a student performs a titration:

The student weighs out $g3.93\text{ g}$ of the amino acid sample, dissolves it in deionised water, and makes the solution up to exactly $cm3250.0\text{ cm}^3$ in a volumetric flask.
A $cm325.0\text{ cm}^3$ sample of $dm−30.150\text{ mol dm}^{-3}$ hydrochloric acid is pipetted into a conical flask.
The amino acid solution is titrated from a burette into the conical flask.
The average titre of the amino acid solution required to reach the end-point is $cm331.25\text{ cm}^3$ .

Nitrogen compounds, polymers and synthesis