Tag: chemistry

Questions Related to chemistry

Which of the following applications reveal that nitrogen is inert?

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. Tinned food products

  2. Making of fertilizers

  3. Refrigerant

  4. Electric bulbs

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Correct Option: A,D
Explanation:

Nitrogen gas is used in food packaging to prolong shelf life and preserve the freshness, integrity, and quality of the delivered product. The presence of oxygen introduces moisture which can deteriorate the food quality.

There is no vacuum in the electric bulb. On the contrary, argon gas or argon gas mixed with a little nitrogen is filled in the bulb under some pressure. Years ago there was a practice to leave vacuum inside the bulb so as to prevent the burning of tungsten filament at high temperature inside the bulb.

Nitrogen can exhibit $+1$ oxidation state.

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. True

  2. False

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Correct Option: A
Explanation:

Nitrogen exhibits several oxidation states, ranging between -3 to +5, which includes +1.

Which of the following is an explosive compound of $N _2$?

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. $N _2O _5$

  2. $NH _3$

  3. $NF _3$

  4. $NCl _3$

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Correct Option: D
Explanation:

$NCl _3$ is explosive. 

Halogen in the +1 oxidation state is a good oxidizing agent and it can oxidize the nitrogen to the highly stable $N _2$ and get itself reduced to $Cl _2$ , both stable gases with a release of energy.
Therefore, NCl3 is explosive.

Hence, option (D) is the correct answer.

The total number of electrons that take part in forming bonds in $N _2$ is:

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. 2

  2. 4

  3. 6

  4. 10

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Correct Option: C
Explanation:

$N \equiv N$
In $N _2$ there are 3 bonds between Nitrogen atoms and each bond is formed by 2 electrons. So, 3 bonds make it $3(2)=6$ electrons in total.

Kjeldahl's method cannot be used for:

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. $PhNO _2$

  2. $PhNHCOPh$

  3. Azobenzene

  4. Pyridine

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Correct Option: A,C,D
Explanation:

Kjeldahl's method is a method for the quantitative determination of nitrogen contained in organic substances as well as nitrogen contained in unorganic compounds ammonia and ammonium.

But, Kjeldahl's method cannot be used for nitrogen determination of compounds having nitro group or azo-group or nitrogen present in rings as the nitrogen of these compounds cannot be converted to ammonium sulphate $(NH _4) _2SO _4$ under the condition of this method.
Hence, option A,C and D.

Kjeldahl's method can be used for estimation of nitrogen in:

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. ${C} _{6}{H} _{5}{NO} _{2}$

  2. Pyridine

  3. ${C} _{6}{H} _{5}N=N{C} _{6}{H} _{5}$

  4. ${C} _{6}{H} _{5}NHCO{CH} _{3}$

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Correct Option: A

Which of the following compound has nitrogen percentage highest?

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. Ammonium nitrate

  2. Ammonium sulphate

  3. Calcium cyanamide

  4. Urea

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Correct Option: A

Nitrogen gas is prepared :

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. by heating ammonium nitrate.

  2. by reacting chlorine with liquor ammonia.

  3. by passing $ HNO _3 $ vapours on red hot copper

  4. by beating lead nitrate.

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Correct Option: A
Explanation:

to prepare pure nitrogen in laboratory a mixture of ammonium chloride and sodium nitrite is heated.  The product formed is ammonium nitrite.  This compound is very unstable and breaks into nitrogen and water.

Dinitrogen is formed when :-

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. Magnesium nitride is heated

  2. Red lead is thermally decomposed

  3. Ammonium nitrite is treated with ${\text{Ba}}{\left( {{\text{OH}}} \right) _{\text{2}}}$

  4. Barium azide is thermally decomposed

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Correct Option: A

(i) $BaC _2+N _2\overset{\Delta}{\rightarrow} (B)$

(ii) $CaC _2+N _2\overset{\Delta}{\rightarrow} (A)$

Identify $(A)$ and $(B)$:

chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

  1. $A: Ca(N=C=N)$ ; B: $Ba(C\equiv N) _2$

  2. $A: Ca(N=C=N)$ ; B:$Ba _2(C\equiv N) _4$

  3. $A: Ca(N=C=N) _2$ ; B:$Ba(C\equiv N) _2$

  4. $A: Ca(N=C=N) _2$ ; B: $Ba _2(C\equiv N) _4$

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Correct Option: A
Explanation:

Reaction:
$CaC _2+N _2\overset{\Delta}{\rightarrow}  Ca(N=C=N)$
$BaC _2+N _2\overset{\Delta}{\rightarrow}  Ba ( CN) _2$