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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

$HCl$ gas cannot be dried by passing through:

  1. $H _{2}SO _{4}$
  2. $CaO$
  3. $P _{2}O _{5}$
  4. $CO$
Reveal answer Fill a bubble to check yourself
B,C Correct answer
Explanation

$CaO$ and $P _2O _5$ are basic in nature so when $HCl$ is based over them, they will react with $HCl$ and form Salt and water, whereas $H _2SO _4$ and $CO$ are an acidic and hence greater affinity for water. So they can be used to dry $HCl$.

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

$HCl$  gas does not effect a dry strip of blue litmus paper but it turns red in the presence of a drop of water ?

  1. Blue litmus paper in the presence of water accepts the proton from $HCl$ and turns blue to red
  2. Blue litmus paper in the presence of water accepts the chloride ion from $HCl$ and turns blue to red

  3. Blue litmus paper in the presence of water with acid do not turn into red

  4. None of the above

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A dry litmus paper will not show any effect in the presence of dry HCL due to the absence of moisture ($H^+$ ions) in the litmus paper, whereas on putting a drop of water, the blue litmus paper immediately turns to red due to the presence of water in it hence presence of hydrogen ions ($H^+$ ions).


Hence, option A 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

When phosphorous pentoxide is reacted with $HCl$ gas, products are:

  1. $POCl _3$
  2. $P _4O _{10}$
  3. $H _3PO _2$
  4. $HPO _3$
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation

Phosphorous pentoxide reacts with $HCl$ to form Phosphorous Oxychloride and metaphosphoric acid.


$2P _2O _5 + 3HCl \rightarrow POCl _3 + 3HPO _3$


Hence, $POCl _3$ and $HPO _3$ are 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

Observing the method of collection of the gas, what you can tell about the density of hydrogen chloride?

  1. A gas that is more dense than air

  2. A gas that is less dense than air

  3. A gas (liqued form ) that is less dense than air

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

A gas that is more dense than air can be collected by downward delivery. Examples of gases that can be collected by this method are carbon dioxide, chlorine, HCl, sulphur dioxide.

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 compound(s) is/are produced when hydrochloric acid is added to silver nitrate solution?

  1. ${ HNO } _{ 3 }$
  2. $AgCl$

  3. Both A and B

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

${ AgNO } _{ 3 }+HCl\rightarrow AgCl+{ HNO } _{ 3 }$

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

$HCl$ is prepared by heating $NaCl$ with $conc.{ H } _{ 2 }S{ O } _{ 4 }$. But $HI$ cannot be prepared by treating $NaI$ with $conc.{ H } _{ 2 }S{ O } _{ 4 }$. Identify the reason.

  1. ${ H } _{ 2 }S{ O } _{ 4 }$ is oxidised by $HI$ and not oxidised by $HCl$
  2. $HI$ is oxidised by ${ H } _{ 2 }S{ O } _{ 4 }$ and $HCl$ is not oxidised by $HI$
  3. $HI$ dissociates on treatment with ${ H } _{ 2 }S{ O } _{ 4 }$ and $HCl$ does not dissociate
  4. Reaction of ${ H } _{ 2 }S{ O } _{ 4 }$ with $HI$ is reversible whereas with $HCl$ is irreversible
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$HCl$ is prepared by heating $NaCl$ with $conc.{ H } _{ 2 }S{ O } _{ 4 }$. But $HI$ cannot be prepared by treating $NaI$ with $conc.{ H } _{ 2 }S{ O } _{ 4 }$. Because  $HI$ is oxidised by ${ H } _{ 2 }S{ O } _{ 4 }$ and $HCl$ is not oxidised by $HI$.

Hence, option $B$ 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

Glaber prepared $HCl$ from which of the following compounds?

  1. $NaCl,H _2SO _4$
  2. $NaCl,H _2CO _3$
  3. $NaCl,HNO _3$
  4. $KCl,H _2SO _4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glaber is the scientist who prepared hydrogen chloride in the laboratory by reacting sodium chloride with concentrated sulphuric acid.

$NaCl+H _2SO _4\rightarrow NaHSO _4+HCl$

Sodium bisulphate is a by-product in the above reaction . This is insoluble. Therefore, we further add it with more sodium chloride. This mixture has to be heated to a higher temperature of around 823K. It gives dissolvable sodium sulfate and HCl gas.

$NaHSO _4+NaCl\rightarrow Na _2SO _4+HCl$.

Hence option $A$ 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 the Hydrolysis of ICl , the products are :

  1. HI +HCl

  2. HI +HOCl

  3. HCl+HOI

  4. HOCl +HOI
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the hydrolysis of ICl, the products are HCl + HOI.


$ICl+H _2O\rightarrow HCl+HOI$

During the hydrolysis of interhalogen compounds, oxyacid of less electronegative or large sized halogen is formed, and other halogen forms halogen acid. 

Thus, less electronegative iodine forms HOI and more electronegative chlorine forms HCl.

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 pain due to honey-bee siting can be relieved by using:

  1. washing soda

  2. water

  3. acid

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

Honey bee sting has formic acid in it which causes irritation and burns.

To neutralise this effect, we recommend a base to be used.
Hence, bee sting can be relieved using baking soda. 

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 acid is used in fire extinguishers?

  1. Hydrochloric acid

  2. Sulphuric acid

  3. Nitric acid

  4. Oxalic acid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Soda-acid extinguisher uses the reaction between sodium bicarbonate solution and sulphuric acid to expel pressurized water onto a fire. The reaction takes place as follows :-

$2NaHCO _3+H _2SO _4 \rightarrow Na _2SO _4+2CO _2+2H _2O$
The $CO _2$ formed forces the water out of the discharge and hence the device must be held in upright position.
However, such extinguisher can't be used in case of fire caused due to electricity (as water is a good conductor of electricity) and fire caused due to oil or petrol (as the oil or petrol may float over water).
Thus, the correct answer is option (B).