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

Slaked lime and chlorine reacts to produce :

  1. quick lime
  2. $CaCl _2$
  3. $CaOCl _2$
  4. mixture of $CaCl _2$ and $Ca(OCl _2)$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$Ca(OH) _2+\underset{\text{dry}}{Cl _2}\xrightarrow{below\,35^oC} \underset{\text{Bleaching powder}}{CaOCl _2 + H _2O}$


$2Ca(OH) _2 + 2Cl _2\xrightarrow{red\, heat} 2CaCl _2 + 2H _2O + O _2\uparrow$

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

The amount of chlorine obtained from a sample of bleaching powder by treatment with excess of dilute acid or $ \displaystyle CO _{2}$ is called available chlorine.

  1. True

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

The available chlorine is defined as the percentage of chlorine made available by bleaching powder when treated with dilute acids. The available chlorine present in bleaching powder sample is determined iodometricaliy by treating its solution with an excess of potassium iodide solution in the acidic medium.

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

Bleaching powder is used :

  1. for bleaching cotton, wood pulp

  2. as a disinfectant and germicide

  3. for the manufacture of chloroform

  4. as a reducing agent in industries
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

Bleaching powder + ethanol $\rightarrow$ chloroform
Bleaching powder is used for bleaching cotton, wood pulp, it is also used as a disinfectant and germicide.

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

Bleaching powder has a strong bleaching action due to:

  1. calcium

  2. chlorine molecule

  3. nascent oxygen

  4. chloride ion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The bleaching powder has a strong bleaching action due to the formation of nascent oxygen.

When bleaching powder reacts with a small amount of acid, it gives nascent oxygen. 
Thus, it acts as an oxidizing agent and thus acts as a bleaching agent.

$2CaOCl _2 +H _2SO _4 \rightarrow CaCl _2+CaSO _4+2HOCl$

$2HOCl \rightarrow 2HCl+2[O]$

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

Which of the following has the strongest bleaching property?

  1. Chlorine

  2. Fluorine

  3. Bromine

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

Chlorine is strongest bleaching property.

Chlorine is a very strong oxidizing agent, which is used commercially as a bleaching agent and as a disinfectant, It is strong enough to oxidize the dyes that give wood pulp its yellow or brown color, for example, thereby bleaching out this color, and strong enough to destroy bacteria and thereby acts as a germicide. 

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 is a correct statement?

  1. Bleaching powder is a compound

  2. Bleaching powder is mixture of calcium chloride and calcium hypochloride

  3. Bleaching powder is a mixture of calcium chloride,calcium hypochlorite and slaked lime

  4. Bleaching powder is a mixture of sodium chloride and sodium hypochloride
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Calcium hypochlorite is an inorganic compound with formula $Ca(ClO) _2$. As a mixture with lime and calcium chloride, it is marketed as chlorine powder or bleach powder for water treatment and as a bleaching agent.
Multiple choice chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

The real bleaching agent present in bleaching powder is:

  1. chlorine

  2. oxygen

  3. CaO

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

Calcium oxychloride (CaOCl2) is known as bleaching powder. In the presence of small amount of dilute acid, it gives nascent oxygen which acts as an oxidising and bleaching agent. When it is treated with excess of dilute acids, chlorine is evolved which is responsible for the bleaching action of bleaching power.