Tag: substances in common use

Quizzes (7) Questions (124)

Questions Related to substances in common use

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

The reaction of $NaCl$ and $CaCO _3$ gives sodium carbonate. But this reaction cannot be used for the manufacture of washing soda since it is a reversible reaction.

  1. True

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

The reaction of $NaCl$ and $CaCO _3$ gives sodium carbonate. But this reaction cannot be used for the manufacture of washing soda since it is a reversible reaction.

$2NaCl+CaCO _3\rightleftharpoons Na _2CO _3+CaCl _2$.

Hence the given statement is True.

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Bleaching powder is soluble in cold water giving a milky solution due to:

  1. available chlorine

  2. lime present in it

  3. calcium carbonate formation

  4. the absorption of carbon dioxide from atmosphere
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bleaching powder on reaction with cold water form milky solution of calcium hydroxide. 

$CaOCl _2+H _2O\rightarrow Ca(OH) _2+Cl _2$

Thus because of the lime present in it, it gives a milky solution when dissolved in water.

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Bleaching powder is obtained by the interaction of $Cl _2$ with a:

  1. dilute solution of $Ca(OH) _2$
  2. concentrated solution of $Ca(OH) _2$
  3. dry $CaO$

  4. dry slaked lime
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$Ca(OH) _2 +Cl _2 \rightarrow Ca(OCl)Cl + H _2O$
Bleaching powder is obtained by the interaction of $Cl _2$ with a dry slaked lime.

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Bleaching powder slowly decomposes to form:

  1. $CaCl _2+Ca(ClO _3) _2$
  2. $CaO+Cl _2$
  3. $CaCl _2+Ca(OCl) _2$
  4. $CaCO _3+Cl _2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When exposed to air, bleaching powder gives a smell of chlorine. This is because bleaching powder reacts with carbon dioxide from the atmosphere to produce calcium carbonate and chlorine.

$Ca(OCl) _2 +CO _2 \rightarrow CaCO _3 +Cl _2$

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

The average oxidation state of chlorine in bleaching power is :

  1. -1

  2. +1

  3. zero

  4. -2 as well as +2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In bleaching powder, $Ca(OCl)Cl$, the two $Cl$ atoms are in different oxidation states i.e., one $Cl^–$ having oxidation number of –1 and the other as $OCl^–$ having oxidation number of +1.


Hence, the average oxidation state of chlorine in bleaching powder is zero.

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Which one of the following processes does not occur during formation of $CH{ Cl } _{ 3 }$ from ${ C H } _{ 3 }OH$ and bleaching powder ?

  1. Hydrolysis

  2. Oxidation

  3. Reduction

  4. Chlorination
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The process that does not occur during the formation of $CHCl _3$ from $CH _3OH$ and Bleaching Powder is REDUCTION PROCESS.
In $CHCl _3$ oxidation state of carbon is +2 and in methanol oxidation state of carbon is-2. This is reduction.
Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Action bleaching poweder on ethyyl alcohol gives?

  1. Chloroform

  2. Dichloro methane

  3. Trichloro ethane

  4. Ethylene chloride
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The reactions involved are-

$CaOCl _2 + H _2O \rightarrow Ca(OH) _2 + Cl _2$

$C _2H _5OH + [O] \rightarrow CH _3CHO$

$CH _3CHO + Cl _2 \rightarrow CCl _3HO$

$CCl _3CHO + Ca(OH) _2 \rightarrow CHCl _3 + (HCOO) _2Ca$


Hence the product formed is having Chloroform and the correct option is A.

Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

Bleaching properties of bleaching powder are due it its:

  1. Oxidizing properties

  2. Reducing properties

  3. Basic properties

  4. Disinfecting properties
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chlorine bleaches by the process of oxidation. It needs moisture for its bleaching action.

Chlorine reacts with water to form hydrochloric and hypochlorous acids.

$Cl _2 + H _2O \rightarrow HCl + HClO$

Hypochlorous acid is unstable, and it easily dissociates to form nascent oxygen.

$HClO \rightarrow HCl + [O]$

Nascent oxygen is a more powerful oxidising agent. Its formation is responsible for the bleaching nature of chlorine in the presence of moisture.

Hence option A is correct answer.