Tag: polymers

Questions Related to polymers

Wood charocal is used in gas masks because it:

  1. has good smell

  2. dissolves poisonous gases

  3. adsorbs poisonous gases

  4. reacts with poisonous gases


Correct Option: C
Explanation:

Activated charcoal is a very good adsorbent. It can easily adsorb large volumes of gases easily. Hence it is used in gas masks to adsorb harmful gases. It cannot adsorb oxygen which makes it perfect for gas masks.

In the preparation of wood charcoal, liquid pyroligneous acid is obtained. It consists of :

  1. acetone

  2. methanol

  3. acetic acid

  4. vinegar


Correct Option: A,B,C
Explanation:

In the preparation of the wood charcoal, the liquid pyroligneous acid is used.
Pyroligneous acids contain acetone, methanol, and acetic acid.

In a test tube, a cotton plug was placed and a few drops of bromine liquid were added to it and then a piece of wood charcoal was added to the test tube. Which of the following are observed?

  1. Initially the test tube is filled with brown vapours

  2. Activated wood charcoal absorbs gases

  3. Brown vapours are retained in the test tube

  4. Brown vapours are formed because of wood charcoal


Correct Option: A,B
Explanation:
Initially, the test tube filled with brown fumes of bromine. They are absorbed by activated wood charcoal which is a good adsorbent and the test tube becomes transparent.

$C _{12}H _{22}O _{11}\xrightarrow{Conc.   H _2SO _4} 12C+11H _2O$
Which of the following is obtained by the above reaction?

  1. Animal charcoal

  2. Sugar charcoal

  3. Coke

  4. Wood charcoal


Correct Option: B
Explanation:

Conc. $H _{2}SO _{4}$ is dehydrating agent. It dehydrates cane sugar to sugar charcoal.

           $C _{12}H _{22}O _{11}\,\,\,\xrightarrow{conc.H _2SO _4}\underset{sugar\ charcoal}{12C}+11H _{2}O$

When superheated steam is passed through white-hot wood charcoal, it gets reduced to a mixture of X and Y and it is named as Z. Identify the mixture Z.

  1. Producer gas

  2. Water gas

  3. Coal gas

  4. Soda water


Correct Option: B
Explanation:

$C\xrightarrow{supre\ heated\ H _2O}CO+H _{2}$


When Superheated steam is passed through white-hot wood charcoal it gets reduced to $CO $ and $H _{2}$. 

This mixture is called $water\ gas$.

When superheated steam is passed through white-hot wood charcoal, it gets reduced to a mixture of X and Y and it is named as Z. Identify Y

  1. $CO _2$

  2. $SO _2$

  3. $H _2$

  4. $NO _2$


Correct Option: C
Explanation:

$C\xrightarrow{supre\ heated\ H _2O}CO+H _{2}$


From the given option Y would be Hydrogen $(H _2)$
Hence, option (C) is correct.

Bone charcoal is prepared by destructive distillation of bones.

  1. True

  2. False


Correct Option: A
Explanation:

Animal charcoal is produced from bones, horn, blood, etc. Bone-black, or bone-charcoal, is obtained by the destructive distillation of bones in iron retorts, the distillate constituting bone- oil or Dippel's oil

Sugar charcoal is prepared by pouring water on sugar syrup.

  1. True

  2. False


Correct Option: B
Explanation:

The given statement is false as sugar charcoal is obtained by removing water and some other volatile constituents from the animal and vegetation substances.

When super heated steam is passed through white hot wood charcoal, it gets reduced to a mixture of $X, Y$ and this reaction is named as $Z$. Identify $X$.

  1. $N{O} _{2}$

  2. $CO$

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

  4. $C{O} _{2}$


Correct Option: B
Explanation:
$X + Y \longrightarrow CO + H _2(water-gas)$
$X = CO$
$Y = H _2$
$XY = water- gas (CO + H _2)$ reaction is exothermic.

$Z$ is known as $ carbonisation$ reaction.
Hence, the correct option is B.

In a test tube, a cotton plug was placed and a few drops of bromine liquid were added to it and then a piece of wood charcoal was added to the test tube. Which of the following are observed?

  1. Initially the test tube is filled with brown vapours

  2. Activated wood charcoal absorbs gases

  3. Brown vapours are retained in the test tube

  4. Brown vapours are formed because of wood charcoal


Correct Option: A,B