Embibe Experts Solutions for Chapter: Qualitative Analysis, Exercise 3: EXERCISE-3

An aqueous solution of a gas $\left(\mathrm{X}\right)$ gives the following reactions:

(i) It decolourises an acidified ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ solution.

(ii) On boiling with ${\mathrm{H}}_2{\mathrm{O}}_2$ and cooling it and then adding an aqueous of ${\mathrm{BaCl}}_2$ in dil. $\mathrm{HCl}$, is produced.

(iii) On passing ${\mathrm{H}}_2\mathrm{S}$ in the solution, white turbidity is formed. Identify the molecular mass of gas $\left(\mathrm{X}\right)$?

The aqueous solution of a inorganic compound $\left(\mathrm{X}\right)$ yielded a white precipitate when treated with dil ${\mathrm{HNO}}_3$ and ${\mathrm{AgNO}}_3$. Another sample of the solution of $\left(\mathrm{X}\right)$ when treated with $\mathrm{NaOH}$ gave a white precipitate first which dissolved in excess of $\mathrm{NaOH}$ yielding a colorless solution. When ${\mathrm{H}}_2\mathrm{S}$ gas was passed through that solution a white precipitate was obtained. Identify the atomic number of cation which is present in compound $\left(\mathrm{X}\right)$?

An orange coloured solid $\left(\mathrm{A}\right)$ can be soluble in water and it gives a gas $\left(\mathrm{B}\right)$ and green coloured solid $\left(\mathrm{C}\right)$ on heating. The compound $\left(\mathrm{A}\right)$ gives a gas $\left(\mathrm{D}\right)$ when reacts with $\mathrm{NaOH}$ and solution turns yellow. The gas $\left(\mathrm{D}\right)$ turns red litmus blue. Identify the molecular mass of gas $\left(\mathrm{B}\right)$?

A compound $\left(\mathrm{X}\right)$ on heating with an excess of $\mathrm{NaOH}$ solution gives a gas $\left(\mathrm{Y}\right)$ which gives white fumes on exposure to $\mathrm{HCl}$. Heating is continued to expel the gas completely. The resultant alkaline solution again liberates the same gas $\mathrm{Y}$ when heated with $\mathrm{Zn}$ power. However, the compound $\left(\mathrm{X}\right)$ when heated alone does not give nitrogen. Identify the atomicity of compound $\left(\mathrm{X}\right)$?

A salt reacts with $\mathrm{NaOH}$ to form a green coloured ppt. $\left(\mathrm{X}\right)$ which is soluble in excess of $\mathrm{NaOH}$. $\left(\mathrm{X}\right)$ on heating gives a green powder $\left(\mathrm{Y}\right). \left(Y\right)$ on fusion with $\mathrm{NaOH}$ in air gives a yellow coloured solution $\left(\mathrm{Z}\right)$. Identify the atomic number of cation in salt $\mathrm{A}$?

An aqueous solution of a gas $\left(\mathrm{X}\right)$ shows the following reactions.

(i) It turns red litmus blue

(ii) When added in excess to a ${\mathrm{CuSO}}_4$ solution, a deep blue colour is obtained

(iii) On addition of ${\mathrm{FeCl}}_3$ solution a brown precipitate soluble in dilute ${\mathrm{HNO}}_3$ is obtained.

Identify the molecular mass of gas $\left(\mathrm{X}\right)$?

A certain metal $\left(\mathrm{A}\right)$ is boiled in dilute ${\mathrm{HNO}}_3$ to give a salt $\left(\mathrm{B}\right)$ and an oxide of nitrogen $\left(\mathrm{C}\right)$. An aqueous solution of $\left(\mathrm{B}\right)$ with brine gives a precipitate $\left(\mathrm{D}\right)$ which is soluble in ${\mathrm{NH}}_4\mathrm{OH}$. On adding aqueous solution of $\left(\mathrm{B}\right)$ to hypo solution, a white precipitate $\left(\mathrm{E}\right)$ is obtained. $\left(\mathrm{E}\right)$ turns black on standing. Identify the atomic number of metal $\left(\mathrm{A}\right)$?

Calcium burns in nitrogen to produce a white power which dissolves in sufficient water to produce a gas $\left(\mathrm{A}\right)$ and an alkaline solution. The solution on exposure to air produces a thin solid layer of $\left(\mathrm{B}\right)$ on the surface. Identify total number of electron in one mole of gas $\left(\mathrm{A}\right)$?