Tag: nitrogen and sulfur

Questions Related to nitrogen and sulfur

Nitrogen molecule is a non polar covalent molecule.

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

  1. True

  2. False

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Correct Option: A
Explanation:

Nitrogen molecule is a non-polar covalent molecule. It has zero dipole moment. Two $N$ atoms in nitrogen molecule have zero electronegativity difference. The bond pairs of electrons are equally distributed between two $N$ atoms.

Which of the following statements is/are true about nitrogen?

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

  1. Its atomic number is $7$

  2. It is very difficult to identify

  3. It is a typical non metal

  4. Ease of formation of triple bond

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Correct Option: A,B,C,D
Explanation:
Nitrogen is a chemical element with the symbol $N$ and atomic number $7$. Nitrogen is commonly referred to as and used as an inert gas (high abundance & low cost). Due to its inert nature it does not react with other compounds. Hence, Nitrogen gas is very difficult to identify because of its nonreactive nature. 
Nitrogen completes its octet state by forming triple bond. 

Choose the correct statement from the following :

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

  1. Nitrogen is neutral to litmus

  2. Nitrogen is a noncombustible and non-supporter of combustion

  3. Nitrogen is a poisonous gas

  4. At low temperature, nitrogen can be liquefied on compression

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Correct Option: A,B,D
Explanation:

Nitrogen is a neutral gas hence, it does not show any change with litmus. Nitrogen is inert at atmospheric conditions. Hence, it is noncombustible nor it does not support combustion.  Liquid nitrogen is nitrogen in a liquid state at an extremely low temperature. Hence, at low temperature, nitrogen can be liquefied on compression. Nitrogen is non-poisonous gas and constitutes around 79% of the air.

Nitrogen is used in high temperature thermometer:

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

  1. to prevent vaporization of mercury

  2. to improve conductivity of mercury

  3. to maintain mercury in its state

  4. to increase the specific heat capacity of mercury

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Correct Option: A,C
Explanation:
In a memory thermometer, nitrogen gas is filled above the mercury which is inert in nature and doesn't react into mercury.
Introduction of nitrogen increases the pressure on the mercury and hence its boiling point is increased.
So it helps to prevent vaporization of memory and hence mercury is maintained in its liquid state and so the range of mercury can be increased up to $800$$° C$
B.P. of mercury $336.7$$° C$

When metal foundry products are cleaned by shot blasting, heat is generated by friction. Nitrogen is used for:

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

  1. providing an inert atmosphere

  2. cooling the blast chamber

  3. reducing friction

  4. displacing hot air

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Correct Option: A
Explanation:
Nitrogen commonly used as inert gas to create inert atmosphere because the strong triple bond needs a lot of energy to break and participate in a reaction. Hence, ${N} _{2}$ is referred as an inert gas.

Which of the following is not a nitrogenous fertilizer ?

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

  1. Calcium cyanamide

  2. CAN

  3. Super phosphate of lime

  4. Urea

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Correct Option: C
Explanation:
Calcium cyanamide ($CaCN _2$) is nitrogenous fertilizer.
CAN is calcium ammonium nitrate and urea $NH _2-CO-NH _2$ is also nitrogenous fertilizer.
Superphosphate of lime, $Ca(H _2PO _4) _2$ is fertilizer of phosphorous.So it's not the fertilizer of nitrogen.
Hence option C is correct.

In Kjeldahl's method, nitrogen present is estimated as:

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

  1. $N _2$

  2. $NH _2$

  3. $NO _2$

  4. none of these

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Correct Option: B
Explanation:

Kjeldahl method is a method that is used the quantitatuin estimation of nitrogen conlaining in inorganic substances like $NH _3/NH _4^+$, and in organic substances.In kjeldah's method, notrogen is estimated in following steps : 

$Step$ $1:$Degradation: Sample$+H _SO _4\longrightarrow {(NH _4)} _2SO _4+CO _2+SO _2+H _2O$
$Step$ $2:$ Ammonia is liberated : ${(NH _4)} _2SO _4+2NaOH\longrightarrow Na _2SO _4+2H _2O+2NH _3$
$Step$ $3:$ Ammonia is captured : $B{(OH)} _3+H _2O+NH _3\longrightarrow NH^+ _4+B{(OH)} _4^-$
$Step$ $4:$ Back titration : $B{(OH)} _3+H _2O+Na _2CO _3\longrightarrow NaHCO _3+NaB{(OH)} _4+CO _2+H _2O$
Thus in Kjeldahl's method, nitrogen present is estimated as $NH _2$.

In the reaction of $2NO+{ O } _{ 2 }\rightarrow 2{ NO } _{ 2 }$, if the rate of disappearance of ${ O } _{ 2 }$ is $16gm$ ${ min }^{ -1 }$, then the rate of apperance of ${ NO } _{ 2 }$ is:

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

  1. $90\ gm\ { min }^{ -1 }$

  2. $46\ gm\ { min }^{ -1 }$

  3. $28\ gm\ { min }^{ -1 }$

  4. $32\ gm\ { min }^{ -1 }$

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Correct Option: A
Explanation:
$2NO+{ O } _{ 2 }\rightarrow 2N{ O } _{ 2 }$
$-\cfrac { 1 }{ 2 } \cfrac { d\left[ NO \right]  }{ dt } =\cfrac { -d\left[ { O } _{ 2 } \right]  }{ dt } =\cfrac { 1 }{ 2 } \cfrac { d\left[ N{ O } _{ 2 } \right]  }{ dt } $
$\cfrac { -d\left[ { O } _{ 2 } \right]  }{ dt } =16ℊ{ min }^{ -1 }=\cfrac { 16 }{ 16 } mol{ min }^{ -1 }=1mol{ min }^{ -1 }$
$\cfrac { d\left[ N{ O } _{ 2 } \right]  }{ dt } =2\times \cfrac { -d\left[ { O } _{ 2 } \right]  }{ dt } =2\times 1=2mol/min$
No. of moles$=\cfrac { weight }{ mol.wt } $
$2\times $Mol. wt of $N{ O } _{ 2 }=$wt
$2\times 46=$ wt $\Rightarrow $Weight of $N{ O } _{ 2 }=92ℊ$
Rate of appearance of $N{ O } _{ 2 }=92ℊ/min\approx 90ℊ/min$
Therefore, option $A$ is correct.

In solid state N2O5 exits as:

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

  1. $[NO3]^ - [NO2]^+$

  2. $[NO2]^ - [NO3]^ +$

  3. $[N2O4]^ + O^-$

  4. $[NO3] [NO2]$

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Correct Option: A
Explanation:

Solid $N _2O _5$ is a salt, consisting of separated anions and cations. The cation is the linear nitronium ion $NO _2^+$ and the anion is the planar nitrate $NO _3^−$ ion. Thus, the solid could be called nitronium nitrate. Both nitrogen centers have oxidation state +5.

$\displaystyle Ca+C _{2} \rightarrow CaC _{2}\xrightarrow{N _{2}}A$
Compound ( A ) is used as a / an :

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

  1. fertilizer

  2. dehydrating agent

  3. oxidising agent

  4. reducing agent

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Correct Option: A
Explanation:

Calcium carbide reacts with nitrogen at high temperature to form calcium cyanamide which is used as fertilizer.
$\displaystyle Ca+C _{2} \rightarrow CaC _{2}\xrightarrow{N _{2}}CaCN _2 + C$