Tag: ammonia

Questions Related to ammonia

In liquid $NH _3$ :

  1. $NH _4CI$ behaves as acid

  2. $NaNH _2$ behaves as base

  3. $CH _3COOH$ behaves as strong acid

  4. all of the above facts are true


Correct Option: D
Explanation:

In liquid $NH _3$,
$NH _4Cl\rightarrow NH _4^++Cl^-$ (acid)
$NaNH _2\rightarrow Na^++NH _2^-$ (base)
$CH _3COOH+NH _3\rightarrow NH _4^++CH _3COO^-$ (acid)

The dissolution of ammonia gas in water does not obey Henry's law. On dissolving, a major portion of ammonia molecules reacts with ${H} _{2}O$ to form ${NH} _{4}OH$ molecules. ${NH} _{4}OH$ again dissociates into ${NH} _{4}^{+}$ and ${OH}^{-}$ ions. In solution therefore, we have ${NH} _{3}$ molecules, ${NH} _{4}OH$ molecules and ${NH} _{4}^{+}$ ions and the following equilibrium exist:

${NH} _{3}(g)$ $ \rightleftharpoons{NH} _{3}(l)+{H} _{2}O{(l)}\rightleftharpoons  {NH} _{4}OH{(aq)}\rightleftharpoons  {NH} _{4}^{+}{(aq)}+{OH}^{-}{(aq)}$

Let, ${c} _{1}$ ${(mol/L)}$ of ${NH} _{3}$ pass in liquid state which on dissolution in water forms ${c} _{2}$ ${(mol/L)}$ of ${NH} _{4}OH$. The solution contains ${c} _{3}$ ${(mol/L)}$ of ${NH} _{4}^{+}$ ions.

Concentration of undissociated ammonium hydroxide is________.
  1. ${c} _{1}+{c} _{2}$

  2. ${c} _{2}-{c} _{3}$

  3. ${c} _{1}+{c} _{3}$

  4. ${c} _{1}-{c} _{2}$


Correct Option: B
Explanation:

${NH} _{3}(g)$$\rightleftharpoons {NH} _{3}(l)+{H} _{2}O\rightleftharpoons  {NH} _{4}OH\rightleftharpoons  {NH} _{4}^{+}+{OH}^{-}$

$c _1$                                                $c _2$                $c _3$
So, remaining moles of undissociated ammonium hydroxide, $NH _4OH=  c _2-c _3$

Aqueous solution of ammonia consists of :

  1. $H^+$ only

  2. $H^-$ only

  3. $NH^+ _4$ only

  4. $NH^+ _4$ and $OH^-$


Correct Option: D
Explanation:
Aqueous solution of ammonia consists of $NH^+ _4$ and $OH^-$.
$NH _3+H _2O\rightarrow NH^{+} _4+OH^{-}$
Hence, option D is correct.

In the absence of catalyst, ammonia is burnt in an atmosphere of oxygen and produces :

  1. nitogen gas and water

  2. nitric oxide

  3. nitrogen dioxide

  4. nitric acid


Correct Option: A
Explanation:

The combustion of ammonia proceeds to yield nitogen gas and water. With the use of catalyst and under correct conditions of temperature, ammonia reacts with oxygen to produce nitric oxide which is oxidized to nitrogen dioxide and is used in the synthesis of nitric acid.

Ammonia is highly soluble in water. Other gases showing similar solubility is/are :

  1. hydrochloric gas

  2. sulphur dioxide gas

  3. chlorine

  4. both A and B


Correct Option: D
Explanation:

Ammonia is highly soluble In water. Two other gases showing similar solubility are hydrochloric gas and sulphur dioxide gas.

Fertilizer obtained from ammonia is/are :

  1. urea

  2. ammonium sulfate

  3. urea ammonium nitrate

  4. all of the above


Correct Option: D
Explanation:

Anhydrous ammonia is the source of nitrogen for other commercial fertilizers, e.g., urea, ammonium sulfate, urea ammonium nitrate etc.

Ammonia on reaction with hypochlorite anion can form:

  1. $NO$

  2. $NH _4Cl$

  3. $N _2H _2$

  4. $HNO _2$


Correct Option: B,C
Explanation:

$NH _3+HOCl \rightarrow NH _4Cl + H _2O$

$2NH _3 + OCl^- \rightarrow N _2H _4 + Cl^- + H _2O$

A bottle of liquor ammonia should be cooled before opening.

  1. True

  2. false

  3. sometimes true sometimes false

  4. none


Correct Option: A
Explanation:

It should be cooled to lower the pressure of ${NH} _{3}$ inside the bottle, otherwise ${NH} _{3}$ will bump out of the bottle.

$NH _{3}$ can enter into complex formation due to:

  1. hydrogen bonding

  2. coordinate bond

  3. covalent bond

  4. ionic bond


Correct Option: B
Explanation:

$NH _3$ can form complex due to the presence of lone pair of electron on $N$, which is donated to a metal to form coordinate bond.

Sodium dissolved in ammonia has blue colour due to:

  1. solvated sodium molecule

  2. amide ion

  3. solvated electron

  4. lone pair of electrons on nitrogen in ammonia


Correct Option: C
Explanation:

Ammonia solution turns blue when alkali and alkaline earth metals are dissolved in it. The blue color of the solution is considered to be due to ammoniated electrons which absorb energy corresponding to red region of the visible light for the their excitation to higher energy levels. The transmitted light is blue which imparts blue color to the solutions.