Tag: nitrogen and sulfur

Questions Related to nitrogen and sulfur

Metal (s) M in the following equation is/are 

${M+N\rightarrow  Metal  nitride}$ :

  1. Na

  2. Li

  3. Cs

  4. Mg


Correct Option: A,B,D
Explanation:

Except from Cs, all these metals form metal nitride $Na _3N, Li _3N, Mg _3N _2$.

At high temperatures,nitrogen directly combines with :

  1. Zn

  2. Mg

  3. Al

  4. Fe


Correct Option: B,C
Explanation:

At high temperatures, nitrogen directly combines with $Mg$ and$ Al$; forms nitride $AlN$ and $Mg _3N _2$.

Write the equation for the formation of ammonia by the action of water on magnesium nitride.

  1. $2{ Mg } _{ 3 }{ N } _{ 2 }+{ 6H } _{ 2 }O\rightarrow { 2NH } _{ 3 }+6Mg\left( OH \right) _{ 2 }$

  2. ${ Mg } _{ 3 }{ N } _{ 2 }+{ 3H } _{ 2 }O\rightarrow { NH } _{ 3 }+3Mg\left( OH \right) _{ 2 }$

  3. $3{ Mg } _{ 3 }{ N } _{ 2 }+{ 6H } _{ 2 }O\rightarrow { 6NH } _{ 3 }+3Mg\left( OH \right) _{ 2 }$

  4. ${ Mg } _{ 3 }{ N } _{ 2 }+{ 6H } _{ 2 }O\rightarrow { 2NH } _{ 3 }+3Mg\left( OH \right) _{ 2 }$


Correct Option: D
Explanation:

${ Mg } _{ 3 }{ N } _{ 2 }+{ 6H } _{ 2 }O\rightarrow { 2NH } _{ 3 }+3Mg\left( OH \right) _{ 2 }$

The following reactions are carried out: 

$A:$ Nitrogen + metal $\rightarrow$ compound $X$
$B:$ $X$ + water $\rightarrow$ ammonia + another compound 
$C:$ Ammonia + metal oxide $\rightarrow$ metal + water + $N _2$

One metal that can be used for reaction $A$ is magnesium. Write the correctly balanced equation for reaction $B$, where $X$ is the compound formed.

  1. ${Na }{ N } _{ 2 }+{ H } _{ 2 }O\rightarrow { NH } _{ 3 }+Na _2O$

  2. ${Mg } _{ 3 }{ N } _{ 2 }+{ 3H } _{ 2 }O\rightarrow { 2NH } _{ 3 }+ 3MgO$

  3. ${Ca } _{ 3 }{ N } _{ 2 }+{ H } _{ 2 }O\rightarrow { NH } _{ 3 }+CaO$

  4. None of these


Correct Option: D
Explanation:

One metal that can be used for reaction A is magnesium. So the corresponding reaction A is $N _2 + 3Mg\rightarrow Mg _3N _2$

Hence the compound X is $-\ Mg _3N _2$.
 

The complete reactions involving $Mg$ are as follows:

A: $N _2 + 3Mg\rightarrow Mg _3N _2$

B: $Mg _3N _2+6H _2O\rightarrow 3Mg(OH) _2+2NH _3$ 

C: $2NH _3+ 3MgO\rightarrow 3Mg+3H _2O+N _2$

The correct balanced equation for reaction B is $Mg _3N _2+6H _2O\rightarrow 3Mg(OH) _2+2NH _3$ 

Match List-I (Compounds) with List-II (Oxidation states of Nitrogen) and select answer using the codes given below the lists.


List - I List - II
$(a)$  $NaN _3$ $(1)$  $+5$
$(b)$  $N _2H _2$ $(2)$  $+2$
$(c)$ $NO$ $(3)$  $-\dfrac{1}{3}$
$(d)$ $N _2O _5$ $(4)$ $- 1$

  1. $a-3\,\quad\,b-4\,\quad\,c-2\,\quad\,d-1$

  2. $a-4\,\quad\,b-3\,\quad\,c-2\,\quad\,d-1$

  3. $a-3\,\quad\,b-4\,\quad\,c-1\,\quad\,d-2$

  4. $a-4\,\quad\,b-3\,\quad\,c-1\,\quad\,d-2$


Correct Option: A
Explanation:

$a−3$
The oxidation state of $N$ in $NaN _3$ is $-1/3$.
The oxidation state of $Na$ is $+1$. So total oxidation state of $3 N$ atoms will be $-1$.

$b−4$
The oxidation state of $N$ in $N _2H _2$ is $-1$.
The oxidation state of $H$ is $+1$. So oxidation state of $N$ atom will be $-1$.

$c−2$
The oxidation state of $N$ in $NO$ is $+2$.
The oxidation state of $O$ is $-2$. So oxidation state of N atom will be $+2$.

$d−1$
The oxidation state of $N$ in $N _2O _5$ is $+5$.
The oxidation state of $O$ is $-2$.
Total oxidation state of $5 O$ atoms will be $5 \times (-2) = -10$.
Total oxidation state of $2 N$ atoms will be $+10$.
So oxidation state of $N$ atom will be $+5$.

Fixation of nitrogen means :

  1. reaction of nitrogen with oxygen

  2. conversion of free atmospheric nitrogen into

    nitrogen compounds

  3. the action of dentrifying bactria on nitrogen

    compounds

  4. decomposition of nitrogenous compounds to

    yield free nitrogen


Correct Option: B
Explanation:

Fixation  - conversion of free atmospheric nitrogen into nitrogen compounds.

Nitrogen can combine directly at higher temperature to give nitrides with :

  1. Mg

  2. Al

  3. Zn

  4. Fe


Correct Option: A,B
Explanation:

Mg and Al give nitrides at higher temperature.
$3Mg + N _{2} \rightarrow Mg _{3}N _{2}$
$Al + \frac{1} {2}N _{2} \rightarrow AlN$

Which of the following is a property of nitrogen?

  1. Supports combustion

  2. Allows combustion

  3. Supports but does not allow combustion

  4. Neither supports nor allows combustion


Correct Option: D
Explanation:
Due to the presence of  a triple bond between two nitrogen atoms of a nitrogen molecule it neither supports nor allows combustion.
Hence option D is correct.

Soil fertilizer contains ______ as a key element.

  1. carbon

  2. nitrogen

  3. oxygen

  4. neon

  5. argon


Correct Option: B
Explanation:

Soil fertilizer contains Nitrogen as a key element.
Nitrogenous fertilizers react with moisture in the soil and produce ammonia which is converted to nitrates by soil bacteria and stored as plant food.

Nitrogen gas is absorbed by :

  1. Aluminium carbide

  2. Calcium carbide

  3. Ferrous sulphate

  4. Calcium hydroxide


Correct Option: D
Explanation:

Nitrogen gas is absorbed by calcium hydroxide at low temperatures.