Question

In the qualitative inorganic analysis of basic radicals, solution is prepared in dilute $HCl$ and then diluted with ${{H}_{2}}O$ before ${{H}_{2}}S$ gas is passed. Orange turbidity appeared in one case on dilution. The radical is $S{{b}^{K+}}$, what is k?

Answer 1

Qualitative inorganic analysis generally known by the name salt analysis. This is generally used to identify the cation and anion present in the inorganic salt. This can be done by conducting a number of tests in a systematic manner and by observing the observations we confirm the absence or presence of specific cations and anions.

Complete answer:
Salt analysis is generally a step by step procedure which can be shown as:
1. First conduct preliminary tests for anion or cation group-wise until you obtain a positive result.
2. Once you get a positive result for a preliminary test for anion or cation then conduct a confirmatory test for anion or cation.
3. Now that the cation and the anion are identified then obtain the chemical formula of the salt by balancing the charges of the cation and anion.
Now in the given example $Sb$ is reacted with HCl and the reaction is shown as:
$2Sb+6HCl\to 2SbC{{l}_{3}}+3{{H}_{2}}$
This further react with water molecules and formed orange precipitates before passing it through ${{H}_{2}}S$ gas, reaction can be shown as:
$SbC{{l}_{3}}+{{H}_{2}}O\to SbOCl+2HCl$
Here the oxidation state of $Sb$ can be calculated as:
$x+(-1)3=0;x=3$, here the value of K is +3.

Note:
In salt analysis acidic and basic radicals are generally discussed on the basis of cations and anions i.e. acidic radicals are generally anion in nature those which have negative charge on them and basic radicals are positively charged known as basic radicals.