Tag: chemistry

Questions Related to chemistry

Match List-I (Compounds) with List-II (Oxidation states of Nitrogen) and select answer using the codes given below the lists.


List - I List - II
$(a)$  $NaN _3$ $(1)$  $+5$
$(b)$  $N _2H _2$ $(2)$  $+2$
$(c)$ $NO$ $(3)$  $-\dfrac{1}{3}$
$(d)$ $N _2O _5$ $(4)$ $- 1$

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

  1. $a-3\,\quad\,b-4\,\quad\,c-2\,\quad\,d-1$

  2. $a-4\,\quad\,b-3\,\quad\,c-2\,\quad\,d-1$

  3. $a-3\,\quad\,b-4\,\quad\,c-1\,\quad\,d-2$

  4. $a-4\,\quad\,b-3\,\quad\,c-1\,\quad\,d-2$

Show answer
Correct Option: A
Explanation:

$a−3$
The oxidation state of $N$ in $NaN _3$ is $-1/3$.
The oxidation state of $Na$ is $+1$. So total oxidation state of $3 N$ atoms will be $-1$.

$b−4$
The oxidation state of $N$ in $N _2H _2$ is $-1$.
The oxidation state of $H$ is $+1$. So oxidation state of $N$ atom will be $-1$.

$c−2$
The oxidation state of $N$ in $NO$ is $+2$.
The oxidation state of $O$ is $-2$. So oxidation state of N atom will be $+2$.

$d−1$
The oxidation state of $N$ in $N _2O _5$ is $+5$.
The oxidation state of $O$ is $-2$.
Total oxidation state of $5 O$ atoms will be $5 \times (-2) = -10$.
Total oxidation state of $2 N$ atoms will be $+10$.
So oxidation state of $N$ atom will be $+5$.

Fixation of nitrogen means :

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

  1. reaction of nitrogen with oxygen

  2. conversion of free atmospheric nitrogen into

    nitrogen compounds

  3. the action of dentrifying bactria on nitrogen

    compounds

  4. decomposition of nitrogenous compounds to

    yield free nitrogen

Show answer
Correct Option: B
Explanation:

Fixation  - conversion of free atmospheric nitrogen into nitrogen compounds.

Nitrogen can combine directly at higher temperature to give nitrides with :

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

  1. Mg

  2. Al

  3. Zn

  4. Fe

Show answer
Correct Option: A,B
Explanation:

Mg and Al give nitrides at higher temperature.
$3Mg + N _{2} \rightarrow Mg _{3}N _{2}$
$Al + \frac{1} {2}N _{2} \rightarrow AlN$

Which of the following is a property of nitrogen?

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

  1. Supports combustion

  2. Allows combustion

  3. Supports but does not allow combustion

  4. Neither supports nor allows combustion

Show answer
Correct Option: D
Explanation:
Due to the presence of  a triple bond between two nitrogen atoms of a nitrogen molecule it neither supports nor allows combustion.
Hence option D is correct.

Soil fertilizer contains ______ as a key element.

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

  1. carbon

  2. nitrogen

  3. oxygen

  4. neon

  5. argon

Show answer
Correct Option: B
Explanation:

Soil fertilizer contains Nitrogen as a key element.
Nitrogenous fertilizers react with moisture in the soil and produce ammonia which is converted to nitrates by soil bacteria and stored as plant food.

Nitrogen gas is absorbed by :

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

  1. Aluminium carbide

  2. Calcium carbide

  3. Ferrous sulphate

  4. Calcium hydroxide

Show answer
Correct Option: D
Explanation:

Nitrogen gas is absorbed by calcium hydroxide at low temperatures. 

Nitrogen molecule is a non polar covalent molecule.

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

  1. True

  2. False

Show answer
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

Show answer
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

Show answer
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

Show answer
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$