Question:
An orange solid (A) on heating gives a green residue (B), a colourless gas (C) and water vapours. The dry gas (C) upon passing over heated Mg gave a white solid (D) which upon subsequent reaction with water gave a gas (E) that gave dense white fumes with HCl. Identify
An orange solid (A) on heating gives a green residue (B), a colourless gas (C) and water vapours. The dry gas (C) upon passing over heated Mg gave a white solid (D) which upon subsequent reaction with water gave a gas (E) that gave dense white fumes with HCl. Identify
Show Hint
Nitrogen is one of the few elements that reacts directly with Magnesium at high temperatures to form a nitride.
Updated On: May 1, 2026
- $Fe(NH_3)_2Cl_2$
- $CuN_2$
- $Mg_3N_2$
- $NH_4Cl$
- $FeCl_2$
Show Solution
Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Concept:
The problem involves a chain of inorganic reactions starting from the thermal decomposition of an ammonium salt.
Step 1: {Analyze the decomposition of the orange solid (A).}
The orange solid is ammonium dichromate. Its heating reaction is: $$(NH_4)_2Cr_2O_7 \rightarrow Cr_2O_3 (\text{Green}) + N_2 (\text{Gas C}) + 4H_2O$$
Step 2: {Reaction of gas (C) with Magnesium.}
Nitrogen gas reacts with heated Magnesium to produce Magnesium nitride (Solid D): $$3Mg + N_2 \rightarrow Mg_3N_2$$
Step 3: {Confirm through hydrolysis of (D).}
Magnesium nitride reacts with water to release Ammonia gas (E): $$Mg_3N_2 + 6H_2O \rightarrow 3Mg(OH)_2 + 2NH_3$$ Ammonia reacts with $HCl$ to form white fumes of $NH_4Cl$.
Step 1: {Analyze the decomposition of the orange solid (A).}
The orange solid is ammonium dichromate. Its heating reaction is: $$(NH_4)_2Cr_2O_7 \rightarrow Cr_2O_3 (\text{Green}) + N_2 (\text{Gas C}) + 4H_2O$$
Step 2: {Reaction of gas (C) with Magnesium.}
Nitrogen gas reacts with heated Magnesium to produce Magnesium nitride (Solid D): $$3Mg + N_2 \rightarrow Mg_3N_2$$
Step 3: {Confirm through hydrolysis of (D).}
Magnesium nitride reacts with water to release Ammonia gas (E): $$Mg_3N_2 + 6H_2O \rightarrow 3Mg(OH)_2 + 2NH_3$$ Ammonia reacts with $HCl$ to form white fumes of $NH_4Cl$.
Was this answer helpful?
0
0
Top KEAM Chemistry Questions
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
- $4\, g$ of copper was dissolved in concentrated nitric acid. The copper nitrate solution on strong heating gave $5\, g$ of its oxide. The equivalent weight of copper is :
- Green chemistry deals with
- Neopentyl bromide undergoes dehydrohalogenation to give alkenes even though it has no $\beta$- hydrogen. This is due to
- Plot of $ log\text{ }x/m $ against log $p$ is a straight line inclined at an angle of $ 45{}^\circ $ . When the pressure is $ 0.5 \,arm $ and Freundlich parameter. $ k $ is $ 10 $ , the amount of solute adsorbed per gram of adsorbent will be $ (log\text{ }5=0.6990) $
View More Questions
Top KEAM Nitrogen Questions
Top KEAM Questions
- i.$\quad$ They help in respiration ii.$\quad$ They help in cell wall formation iii.$\quad$ They help in DNA replication iv. $\quad$They increase surface area of plasma membrane Which of the following prokaryotic structures has all the above roles?
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- If $\int e^{2x}f' \left(x\right)dx =g \left(x\right)$, then $ \int\left(e^{2x}f\left(x\right) + e^{2x} f' \left(x\right)\right)dx =$
View More Questions