Tag: ammonia and fertilizers

Questions Related to ammonia and fertilizers

$NH _4CI, NH _4NO _3$ and $(NH _4) _2CO _3$ gives $NH _3$ gas on heating.

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. True

  2. False

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Correct Option: B
Explanation:

Reaction:
$NH _4NO _3\rightarrow N _2O+2H _2O$
$NH _4Cl\rightarrow NH _3+HCl$
$(NH _4) _2CO _3\rightarrow 2 NH _3 + H _2O + CO _2$

Which of the following is/are correct?

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. Hydrolysis of $NCl _3$ gives $NH _3$ and $HClO$

  2. $NH _3$ is less stable than $PH _3$

  3. $NH _3$ is a weak reducing agent compared to $PH _3$

  4. Nitric oxide is paramagnetic

Show answer
Correct Option: A,C,D
Explanation:

A) $NCl _3$ is hydrolyzed by hot water to release ammonia and hypochlorous acid.
 $NCl _3 + 3H _2O\rightarrow NH _3 + 3HOCl$

B)  $NH _3$ is less stable than $PH _3$, because $NH _3$ is more stable than $PH _3$ due to inter molecular hydrogen bonding.
C) $NH _3$ is a weak reducing agent compared to $PH _3$, because from $NH _3$ to $PH _3$ reducing nature increases down the group.
D) Nitric oxide is paramagnetic, because it is having unpaired electrons.
Hence, options A,C & D are correct.

Ammonia is not a product in the :

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. hydrolysis of nitrolim

  2. hydrolysis of aluminium nitride

  3. decomposition of ammonium nitrite

  4. hydrolysis of urea

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Correct Option: C
Explanation:

$NH _3NO _3\rightarrow N _2O+2H _2O$
Nitrous oxide is produced after decomposition of ammonium nitrite instead of ammonia.

 Which compound does not give ammonia gas on reaction with water ?

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. $ \mathrm{M}\mathrm{g} _{3}\mathrm{N} _{2}$

  2. $ \mathrm{A}\mathrm{l}\mathrm{N}$

  3. $\mathrm{C}\mathrm{a}\mathrm{C}\mathrm{N} _{2}$

  4. $\mathrm{C}\mathrm{a}(\mathrm{C}\mathrm{N}) _{2}$

Show answer
Correct Option: D
Explanation:
$Mg _3N _2 + 6H _2O \longrightarrow3Mg(OH) _2 + 2NH _3$

$AlN + 3H _2O \longrightarrow NH _3 + Al(OH) _3$

$2H _2O + Ca(CN) _2 \longrightarrow Ca(OH) _2 + 2HCN$

$CaCN _{2} + 3H _{2}O\longrightarrow$ $CaCO _{3} + 2NH _{3}$

$Ca(CN) _2$ does not produce ammonia on reacting with water.

Assertion (A): In the synthesis of ammonia by Haber's process, mixture of potassium and aluminium oxides can be used as promoter.
Reason (R): Promoter enhances the activity of catalyst.

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. Both (A) and (R) are true and (R) is the correct explanation of (A)

  2. Both (A) and (R) are true and (R) is not the correct explanation of (A)

  3. (A) is true and (R) is false

  4. (A) is false but (R) is true

Show answer
Correct Option: A
Explanation:

Promoter enhances the activity of catalyst (here iron), and because of which potassium and aluminium oxides are used as promoter in Haber's process.

Assertion (A): A mixture of $CaCN _2$ and graphite is known as nitration mixture.
Reason (R) : $NH _3$ is collected by downward displacement of air.

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. Both (A) and (R) are true and (R) is the correct explanation of (A)

  2. Both (A) and (R) are true and (R) is not the correct explanation of (A)

  3. (A) is true and (R) is false

  4. (A) is false but (R) is true

Show answer
Correct Option: D
Explanation:

$HNO _{3}+H _{2}SO _{4}$ is known as nitration mixture. So, A is wrong.
$NH _{3}$ is collected by downward displacement of air as $NH _{3}$ is lighter than air.

The gas oxygen from thermal decomposition of $\displaystyle (NH _4) _2 \, Cr _2 O _7 $ :

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. Oxygen

  2. Nitric oxide

  3. Ammonia

  4. Nitrogen

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Correct Option: D
Explanation:

$\displaystyle (NH _4) _2 \, Cr _2O _7 \, \overset{\Delta}{\longrightarrow} Cr _2O _3 + N _2 + 4H _2O $

In Haber process of  Ammonia production the element used as catalytic promoter to increase the activity of Iron catalyst is .......................

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. NI (Nickel)

  2. W (Tungston)

  3. V (Vanadium)

  4. Mo (Molybednum)

Show answer
Correct Option: D
Explanation:

In Haber process of  ammonia production the element used as catalytic promoter to increase the activity of Iron catalyst is Mo (Molybednum).
$N _2+3H _2  \rightleftharpoons 2NH _3 + 24 \quad kcal$
The temperature is $450^oC$ and  the pressure is 200-250 atm.

The wrong statements about $\displaystyle NH _{3}$ is :

chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. it is oxidised with oxygen at $\displaystyle 700^{\circ}C$ in the presence of platinum

  2. it gives black precipitate with calomel

  3. it can be dried by $\displaystyle P _{2}O _{5},\ H _{2}SO _{4}\, $and$\, CaCl _{2}$

  4. it gives white fumes with HCI

Show answer
Correct Option: C
Explanation:
$NH _3$ is oxidised to nitric oxide and water with oxygen at $700^oC $ in the presence of platinum.
Aqueous ammonia reacts with calomel $Hg _2Cl _2$ to produce metallic mercury, a black precipitate. 
$CaO$ calcium oxide is used for drying of ammonia. Because $CaO$ being basic in nature does not react with $NH _3$ while $P _2O _5, $ conc. $H _2SO _4 \ $and$ \ CaCl _2$ reacts with it.
$CaO + H _2O + NH _3 \rightarrow NH _3 + Ca(OH) _2$
$CaCl _2 + 8NH _3 \rightarrow CaCl _2.8NH _3$
$P _2O _5 + 3H _2O + 6NH _3 \rightarrow 2(NH _4) _3PO _4$
$H _2SO _4 + NH _3 \rightarrow (NH _4) _2SO _4$
$NH _3$ gives White fumes of $NH _4Cl$ with $HCl$.
Nitrogen reacts with a metal $M$ to produce a compound $X$. This compound $X$ when dissolved in water forms pungent gas $Y$ which can be identified easily by the formation of white fumes in the presence of $HCl$.

Identify Y:
chemistry nitrogen and sulfur ammonia and fertilizers preparation of ammonia-laboratory method and haber's process ammonia

  1. Nitrogen dioxide

  2. Ammonia

  3. Nitrous oxide

  4. Nitric oxide

Show answer
Correct Option: B
Explanation:
$ 3Ca+{ N } _{ 2 }\xrightarrow [ \Delta  ]{  } { Ca } _{ 3 }{ N } _{ 2 } $

$ { Ca } _{ 3 }{ N } _{ 2 }+6{ H } _{ 2 }O\xrightarrow [  ]{  } 3Ca{ (OH) } _{ 2 }+2N{ H } _{ 3 } $
From the reaction we can see that the metal $ M $ is $Ca$ and pungent gas $ Y $ is Ammonia.