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Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

When excess of ammonia is used:


 $3Cl _2+8NH _3$$\longrightarrow$$A+B$

When excess of chlorine is used:

$3Cl _2+4NH _3$$\longrightarrow$$C+D$

The oxidation state of nitrogen in compound $D$ is:

  1. $0$
  2. $+3$
  3. $-3$
  4. $+1$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When excess chlorine reacts with ammonia (3Cl2 + 4NH3), the products are nitrogen trichloride (NCl3) and HCl. In NCl3, nitrogen is bonded to three more electronegative chlorine atoms, giving nitrogen an oxidation state of +3.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

An alkaline earth metal $(M)$ dissolves in liquid ammonia forming a deep blue-black solution. The reaction involved is:

  1. $M + 2NH _{3} \rightarrow M(NH _{2}) _{2} + H _{2}$
  2. $M + xNH _{3} \rightarrow [M(NH _{3}) _{x}]$
  3. $M + 2NH _{4}OH \rightarrow M(OH) _{2} + 2NH _{3}$
  4. $M + (x + 2y) NH _{3}\rightarrow [M(NH _{3}) _{x}]^{2+} + 2[e(NH _{3}) _{y}]^{-}$. (e represents electron)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An alkaline earth metal $(M)$ dissolves in liquid ammonia forming a deep blue-black solution. The reaction involved is $M + (x + 2y) NH _{3}\rightarrow [M(NH _{3}) _{x}]^{2+} + 2[e(NH _{3}) _{y}]^{-}$ (e represents electron).
An alkaline earth metal $(M)$ will lose two electrons to form $M^{2+}$ ions.
$M \rightarrow M^{2+}+2e^-$
Both $M^{2+}$ ions and electrons are solvated (surrounded by ammonia molecules to form $[M(NH _{3}) _{x}]^{2+} + 2[e(NH _{3}) _{y}]^{-}$).

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

The organic compound which was first prepared in the laboratory ?

  1. Acetic acid

  2. Methane

  3. Urea

  4. All of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Urea was first discovered in urine in 1727 by the Dutch scientist Herman Boerhaave, This was the first time an organic compound was artificially synthesized from inorganic starting materials, without the involvement of living organisms.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Select the correct options about the solubility of the following species in $ H _2O$ and $ NH _3 $(aq).
$AgF, AgCN, AgCl, Agl, CaF _2, CaCl _2 $ :

  1. $AgF$ and $CaCl _2 $ are soluble in $H _2O$
  2. $AgCN$ and $AgCl$ are soluble in $NH _3$
  3. $AgI$ and $CaF _2$ are soluble in $ H _2O $ and $ NH _3 $ (aq) both

  4. None of these
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

A. $AgF$ and $CaCl _2$ are polar compounds. Hence, they are soluble in water which is a polar solvent. Thus, the option A is correct.

B. $AgCN$ and $AgCl$ form complexes with ammonia as ammonia is a very good ligand. Hence, $AgCN$ and $AgCl$ are soluble in ammonia. Thus, the option B is correct.

C. $CaF _2$ and $AgI$ are insoluble in water. Thus, the option C is incorrect.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Which has the highest $pK _b$ value ?

  1. $R _3N$
  2. $R _2NH$
  3. $RNH _2$
  4. $NH _3$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ammonia is a weak base so it has pK value of 4. So the order of basicity is ammonia<primary<tertiary amines <secondary amines. This order depends on steric hindrance. The size of alkyl group is more than that of hydrogen atom. So alkyl group hinders the attack of hydrogen atom and decreases the basicity of molecule. So more the number of alkyl groups lesser will be its basicity.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Which of the following forms hydrogen bond?

  1. $\displaystyle { CH } _{ 4 }$
  2. $\displaystyle { CO } _{ 2 }$
  3. $\displaystyle { NH } _{ 3 }$
  4. $\displaystyle { N } _{ 2 }$
  5. $\displaystyle { O } _{ 2 }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hydrogen bonding occurs when hydrogen is covalently bonded to a highly electronegative atom like nitrogen, oxygen, or fluorine. Ammonia (NH3) satisfies this condition.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Statement 1: $NH _{3}$ can be best collected by water displacement.

Statement 2: $NH _{3}$ is a polar substance.

  1. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1</p>

  2. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation of Statement 1</p>

  3. <p>Statement 1 is correct but Statement 2 is not correct</p>

  4. <p>Statement 1 is not correct but Statement 2 is correct</p>

  5. <p>Both the Statement 1 and Statement 2 are not correct</p>
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nitrogen, oxygen and hydrogen can be collected by water displacement because they are only slightly soluble in water. But hydrogen chloride or ammonia can not be separated since both are very highly soluble in water and will react to form hydrochloric acid or ammonium hydroxide respectively so statement 1 is not true.

$NH _3$ is a polar substance so statement 2 is correct.