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Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

HCl can be prepared by:

  1. $NaCl$ + $H _{2}SO _{4}$$\overset{420K}\rightarrow$
  2. $NaHSO _{4}$ + $NaCl$ $\overset{823K}\rightarrow$
  3. $NaNO _3$ + $H _{2}SO _{4}$ $\rightarrow$

  4. both (A) and (B).
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
HCl can be prepared by following :

$NaCl$ + $H _{2}SO _{4}$$\overset{420K}\rightarrow NaHSO _4+HCl$

$NaHSO _{4}$ + $NaCl$ $\overset{823K}\rightarrow Na _2SO _4+HCl$.

Hence option D is correct.
Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

In which reaction equilibrium moves in left hand side when pressure is increased?

  1. $H _{2(g)} + Cl _{2(g)} \rightleftharpoons 2HCl _{(g)}$
  2. $2Mg _{(s)} + O _{2(g)} \rightleftharpoons 2MgO _{(s)}$
  3. $2H _{2}O _{(g)} \rightleftharpoons 2H _{2(g)} + O _{2(g)}$
  4. $N _{2(g)} + 3H _{2(g)} \rightleftharpoons 2NH _{3(g)}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

According to Le Chatelier's principle, increasing pressure shifts the equilibrium toward the side with fewer moles of gas. In reaction C, there are 2 moles of gas on the left and 3 moles on the right. Increasing pressure shifts it to the left (fewer moles).

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification
Formation of $HCl$ from its elements takes place in the presence of sunlight.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hydrogen chloride is prepared from chlorine gas and hydrogen gas in the presence of UV light. This reaction is exothermic and the resulting HCl gas is absorbed in deionized water.

${ H } _{ 2 }+{ Cl } _{ 2 }\rightarrow 2HCl$

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

The compound which does not have oxygen is :

  1. nitric acid

  2. sodium hydroxide

  3. hydrochloric acid

  4. acetic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Nitric acid $(HNO _3)$ has 3 oxygen atoms in its formula.

Sodium hydroxide $(NaOH)$ has 1 oxygen atom in its formula.
Acetic acid $(CH _3COOH)$ has 2 oxygen atoms in its formula.
Hydrochloric acid $(HCl)$ does not have oxygen atom in its formula.

Hence, option C is correct.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Identify the gas evolved when potassium sulphite is treated with dilute hydrochloric acid.

  1. ${ S } _{ 2 }$
  2. ${ O } _{ 2 }$
  3. ${ SO } _{ 2 }$

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When potassium sulphite is treated with dilute hydrochloric acid, sulphur dioxide gas is evolved along with potassium chloride and water.


$ { K } _{ 2 }{ SO } _{ 3 }+HCl\rightarrow KCl + { H } _{ 2 }O+{ SO } _{ 2 }$

Hence, option C is correct.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Which of the following gas is evolved when concentrated hydrochloric acid is made to react with manganese dioxide?

  1. ${ O} _{ 3 }$
  2. ${ O } _{ 2 }$
  3. ${ H} _{ 2 }$
  4. ${ Cl } _{ 2 }$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When concentrated hydrochloric acid reacts with manganese dioxide, chlorine gas as well as manganese(II) chloride and water. 


${ MnO } _{ 2 }+4HCl\rightarrow { MnCl } _{ 2 }+{ Cl } _{ 2 }+2{ H } _{ 2 }O$

Hence, option $\text{D}$ is correct.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Iron reacts with hydrogen chloride gas-forming (iron [II] chloride, iron [III] chloride) and hydrogen, The reaction is an example of :

  1. double decomposition

  2. synthesis

  3. simple displacement

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Iron reacts with hydrogen chloride gas-forming iron$ [II] $ chloride and hydrogen. The reaction is an example of simple displacement reaction.


$Fe + 2HCl \longrightarrow FeCl _2 + H _2$


Hence, the correct answer is option $\text{D}$.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Hydrochloric acid can be converted into chlorine by heating with :

  1. calcium oxide

  2. lead [III] oxide

  3. lead [IV] oxide

  4. lead [II] oxide
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Explanation :-

In $HCl$, the chlorine atom present with $-1$ oxidation state and $Cl _2$ has zero oxidation state. It means chlorine undergoes reduction that is only possible in the presence of a strong oxidizing agent.

$\underset{agent (Pb \ in \ +4 \ state)}{\underset{strong \ oxidizing}{PbO _2}} + 4HCl \rightarrow PbCl _2 + Cl _2 + 2H _2O$

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Compounds $A$ and $B$ are treated with dilute $HCl$ separately. The gases liberated are $Y$ and $Z$ respectively $Y$ turns acidified dichromate paper green while $Z$ turns lead acetate paper black. So $A$ and $B$ compounds are respectively:

  1. $Na _2SO _3, Na _2S$
  2. $NaCl, Na _2CO _3$
  3. $Na _2S, Na _2SO _3$
  4. $Na _2SO _3, K _2SO _4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Na2SO3 + HCl produces SO2 gas, which turns acidified dichromate paper green. Na2S + HCl produces H2S gas, which turns lead acetate paper black. Thus, A is Na2SO3 and B is Na2S.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

On adding few drops of dil. HCl to freshly precipitated ferric hydroxide, a red coloured colloidal solution is obtained. The phenomenon is known as :

  1. protective action

  2. flocculation

  3. coagulation

  4. peptisation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Peptization is the process of forming stable colloids by using an electrolyte to break up a precipitate and disperse it into the colloid


Hence, option D is correct.