Tag: ammonia

Questions Related to ammonia

Ammonia gas cannot be dried by passing through :

  1. $conc.{ H } _{ 2 }S{ O } _{ 4 }$

  2. anhydrous $CaO$

  3. ${ P } _{ 2 }{ O } _{ 5 }$

  4. $CuS{ O } _{ 4 }$


Correct Option: A,C
Explanation:

Because ammonia and water will form some amount of ammonium hydroxide, $N{ H } _{ 4 }OH$. The hydroxide will react with the acid ${ H }^{ + }$ ions from the acid and forms water. Addition of an acid to even a mild base like $N{ H } _{ 4 }OH$ is counter-productive to drying.

Identify the probable products for the reaction of $N{ H } _{ 3 }$ with ${ Cl } _{ 2 }$.

  1. ${ N } _{ 2 }$ and $N{ H } _{ 4 }Cl$

  2. $N{ Cl } _{ 3 }$ and $HCl$

  3. ${ N } _{ 2 }$ and $N{ Cl } _{ 3 }$

  4. $N{ H } _{ 4 }Cl$ and $HCl$


Correct Option: A,B
Explanation:

Possible reactions of $N{ H } _{ 3 }$ and ${ Cl } _{ 2 }$ are :

  1. $N{ H } _{ 3 }+{ Cl } _{ 2 }\longrightarrow { N } _{ 2 }+N{ H } _{ 4 }Cl$
  2. $N{ H } _{ 3 }+{ Cl } _{ 2 }\longrightarrow N{ C }l _{ 3 }+HCl$

Which of the following has highest proton affinity:

  1. Stilbine

  2. Arsine

  3. Phosphine

  4. Ammonia


Correct Option: D
Explanation:

As the size of the nitrogen in ammonia is less than the other elements in the hydrides of that group ammonia has the more affinity towards the proton than the any other hydride of that group like phosphine, stobine and arsine.
Hence option D is correct.

The chemical used for cooling in refrigeration is:

  1. $CO _2$

  2. $NH _4OH$

  3. $NH _4Cl$

  4. liq. $NH _3$


Correct Option: D
Explanation:

Its vaporization property, ammonia is an used as a refrigerant. It was used earlier to the use of chlorofluorocarbons (Freons). Anhydrous ammonia is widely used in industrial refrigeration.

$NH _3$ gas is liquefied more easily than $N _2$. Hence:

  1. vander Waals' constants a and b of $NH _3$ > that of $N _2$

  2. vander Waals' constants a and b of $NH _3$ < that of $N _2$

  3. $a(NH _3)$ > $a(N _2)$ but $b(NH _3)$ < $b(N _2)$

  4. $a(NH _3)$ < $a(N _2)$ but $b(NH _3)$ > $b(N _2)$


Correct Option: C
Explanation:
  • In vander Wall's equation of state, the constant 'a' provides a correction for the intermolecular forces. Constant 'b' is a correction for finite molecular size and its value is the volume of one mole of the atoms or molecules.
  • For a gas which is easily liquifiable value of 'a' will be more and value of 'b'  will be less.
  • Hence in the question it is given that $NH _3$ is liquefied more easilt than $N _2$ and hence $a(NH _3)>a(N _2)$ but $b(NH _3)<b(N _2)$.

Which compound form linear polymer due to H-bond :

  1. H2O

  2. NH3

  3. HBr

  4. HCl


Correct Option: B
Explanation:

$NH _3$ forms linear polymer due to Hydrogen bonding. Intermolecular Hydrogen bonding occurs between Nitrogen of one molecule and Hydrogen of other molecule. This continues and makes it a linear polymer.

What is the amount of hear released when $3.4$ gm $NH _3$(g) and $6.4$gm $O _2$(g) react at constant temperature and pressure by the following equation.
$4NH _3$(g) + $5O _2$ (g) \rightarrow $4NO(g)$ + $6H _2O$(g) . $\Delta _1H^0 = 900 k.$

  1. $45$ kJ

  2. $250$ kJ

  3. $36$ kJ

  4. None of these


Correct Option: C
Explanation:

The molecular weights of $\displaystyle NH _3$ and $\displaystyle O _2$ are 17 g/mol and 32 g/mol respectively.
3.4 g $\displaystyle NH _3 = \dfrac {3.4 \ g}{ 17 \ g/mol}=0.2 \ mol$
6.4 g $\displaystyle O _2= \dfrac {6.4 \ g}{32 \ g/mol}=0.2 \ mol$
0.2 moles of $\displaystyle O _2$ will react with $\displaystyle 0.2 \times \dfrac {4}{5}=0.16$ moles of $\displaystyle NH _3$. But 0.2 moles of
$\displaystyle NH _3$ are present. Hence, $\displaystyle O _2$ is the limiting reagent and $\displaystyle NH _3$ is excess reagent.

When 5 moles of $\displaystyle O _2$ react, the heat released is 900 kJ.
When 0.2 moles of $\displaystyle O _2$ react, the heat released will be
$\displaystyle 900 \ kJ \times \dfrac { 0.2}{5}=36 \ kJ$.

Hypotism is a powerful art of suggestion. Under the influence of hypnotism, subjects may report as normal, a slightly smell from:

  1. A source of pure hydrogen gas

  2. An ammonia bottle

  3. An oxygen cylinder

  4. A source of pure nitrogen gas


Correct Option: B
Explanation:

Ammonia has a strong smell which can be easily detected even from meters of distances. Hence, a slight smell of ammonia bottle can be detected.

Ammonia gas on passing through copper sulphate solution gives:

  1. yellow colour solution

  2. blue colour solution

  3. brown colour solution

  4. red colour solution


Correct Option: B
Explanation:

Ammonia reacts with copper(II)ions to precipitate light blue copper hydroxide. Ammonia causes the copper ion to go back into the solution as a deep blue ammonia complex. The precipitate dissolves as we add an excess of ammonia.

Which of the following chemicals has caused disasters by exploding in the holds of ships in harbours and in warehouses?

  1. Vinegar in bottles under pressure

  2. Ammonium nitrate

  3. Gold chloride

  4. Caustic soda


Correct Option: B
Explanation:

Ammonium Nitrate caused an explosion at the Port of Texas City. A ship loaded with $NH _4NO _3$ docked at the Port erupted in flames.

Another ship also carrying $NH _4NO _3$ caught fire in the blast and exploded on the same day.