Practical Organic Chemistry

In Carius tube, an organic compound '\(\mathrm{X}\)' is treated with sodium peroxide to form a mineral acid 'Y'.

The solution of \(\mathrm{BaCl}_{2}\) is added to '\(\mathrm{Y}\)' to form a precipitate 'Z'. 'Z' is used for the quantitative estimation of an extra element. '\(\mathrm{X}\)' could be