Tag: ammonia and fertilizers

Questions Related to ammonia and fertilizers

How is ammonia collected?

  1. Ammonia is less dense than air so it is collected by upward delivery.

  2. Ammonia is more dense than air so it is collected by upward delivery.

  3. Ammonia is more dense than air so it is collected by downward delivery.

  4. None of the above.


Correct Option: A
Explanation:

Ammonia is less dense than air so it is collected by upward delivery or gas syringe method.
In upward delivery method a gas jar is connected by a tube to flask that is giving off gas. The gas that is less dense than air rises to the top of gas jar. The air in the gas jar is displaced until the gas jar is filled with collected gas. Ammonia is very soluble gas so the collection apparatus should be dry and not collected over water.

Write the balanced equation for the preparation of $NH _3$ from ammonium chloride and calcium hydroxide.

  1. ${ 4NH } _{ 4 }Cl+Ca\left( OH \right) _{ 2 }\rightarrow 2{ NH } _{ 3 }+2{ CaCl } _{ 2 }+{ 2H } _{ 2 }O$

  2. ${ 2NH } _{ 4 }Cl+2Ca\left( OH \right) _{ 2 }\rightarrow 2{ NH } _{ 3 }+2{ CaCl } _{ 2 }+{ 2H } _{ 2 }O$

  3. ${ 2NH } _{ 4 }Cl+Ca\left( OH \right) _{ 2 }\rightarrow 2{ NH } _{ 3 }+{ CaCl } _{ 2 }+{ 2H } _{ 2 }O$

  4. ${ NH } _{ 4 }Cl+Ca\left( OH \right) _{ 2 }\rightarrow { NH } _{ 3 }+{ CaCl } _{ 2 }+{ 2H } _{ 2 }O$


Correct Option: C
Explanation:

${ 2NH } _{ 4 }Cl+Ca\left( OH \right) _{ 2 }\rightarrow 2{ NH } _{ 3 }+{ CaCl } _{ 2 }+{ 2H } _{ 2 }O$

Warming ammonium sulphate with sodium hydroxide solution gives :

  1. ammonia

  2. chlorine

  3. nitrogen

  4. none of these


Correct Option: A
Explanation:

$(NH _4) _2SO _4 + 2NaOH \rightarrow Na _2SO _4 + 2H _2O + 2NH _3$

Heating ammonium chloride with sodium hydroxide produces :

  1. ammonia

  2. nitrogen

  3. chlorine

  4. none of these


Correct Option: A
Explanation:

$NH _4Cl + NaOH \rightarrow H _2O + NH _3 + NaCl $

Which reaction of ammonia forms the first step of Ostwald's process?

  1. The catalytic oxidation of ammonia by platinum catalyst

  2. The catalytic oxidation of ammonia by cobalt catalyst

  3. The catalytic reduction of ammonia by platinum catalyst

  4. The oxidation of ammonia


Correct Option: A
Explanation:

The first step of Ostwald's process is the catalytic oxidation of ammonia by platinum catalyst for the formation of nitric acid.

$NH _3+O _2 \xrightarrow {Pt} NO+ H _2O$

$N _2(g) + 3H _2(g)\overset{Fe+Mo}{\rightleftharpoons}2NH _3(g)$; Haber's process.

Mo is used as :

  1. a catalyst

  2. a catalytic promoter

  3. an oxidising agent

  4. a catalytic poison


Correct Option: B
Explanation:

$NH _3$ is manufactured by Haber's process.
$N _2(g) + 3H _2(g)\overset{Fe+Mb}{\rightleftharpoons}2NH _3(g)$
In this process, pure nitrogen and hydrogen gases react in the ratio of $1:3$ by volume in $400^0C-500^0C$ temperature, $200-900$ atm pressure in presence of iron as catalyst and Mo as promoter.

A mixture of $NH _4Cl$ and $NaCl$ can be separated by

  1. filtration

  2. Distillation

  3. Sublimation

  4. Decantation


Correct Option: C
Explanation:

$NH _4$ undergoes sublimation while NaCI does not.

 In commercial industry, ammonia is prepared by :

  1. decomposition of salts

  2. contact process

  3. arc process

  4. combining  hydrogen and nitrogen gases (Haber process)


Correct Option: D
Explanation:

 In commercial industry, ammonia is prepared by combining hydrogen and nitrogen gases (Haber process).
$N _2 + 3H _2 \rightleftharpoons 2NH _3+24\ kcal$

What are the missing products of the following reaction? $\displaystyle { NH } _{ 4 }Cl+{ Ca\left( OH \right)  } _{ 2 }\rightarrow \ _ \ _ \ _ +Ca{ Cl } _{ 2 }$

  1. $\displaystyle { N } _{ 2 }$

  2. $\displaystyle { NH } _{ 3 }$

  3. $\displaystyle { H } _{ 2 }O$

  4. $\displaystyle { NH } _{ 3 }+{ N } _{ 2 }$

  5. $\displaystyle { NH } _{ 3 }+{ H } _{ 2 }O$


Correct Option: E
Explanation:

Calcium hydroxide reacts with ammonium chloride to give ammonia, water and calcuim chloride.

${ 2NH } _{ 4 }Cl+Ca{ (OH) } _{ 2 }\rightarrow { 2NH } _{ 3 }+{ 2H } _{ 2 }O+{ CaCl } _{ 2 }$

Pressure is increased in the Haber process for making ammonia. It favors :

  1. the reverse reaction

  2. the forward reaction

  3. neither reaction

  4. none


Correct Option: B
Explanation:

Pressure is increased in the Haber process for making ammonia. It favors the forward reaction.
$\displaystyle N _2 + 3H _2 \rightarrow 2NH _3$
The reaction proceeds with decrease in the number of moles of gaseous species. With increase in pressure, the equilibrium shifts in forward direction with decrease in the number of moles of gaseous species so that, the effect of increased pressure is nullified.