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Multiple choice biochemical polymers polymerisation chemistry

Match the column I with column II and mark the appropriate choice

Column I Column II
(A) Peptide linkage (i) Inversion
(B) Nucleic acid (ii) Polysaccharide
(C) Hydrolysis of cane sugar (iii) Proteins
(D) Starch (iv) Nucleotides
  1. (A) $\rightarrow$ (i); (B) $\rightarrow$ (i); (C) $\rightarrow$ (iii); (D) $\rightarrow$ (iv)
  2. (A) $\rightarrow$ (iv); (B) $\rightarrow$ (i); (C) $\rightarrow$ (ii); (D) $\rightarrow$ (iii)
  3. (A) $\rightarrow$ (iii); (B) $\rightarrow$ (iv); (C) $\rightarrow$ (i); (D) $\rightarrow$ (ii)
  4. (A) $\rightarrow$ (i); (B) $\rightarrow$ (iii); (C) $\rightarrow$ (iv); (D) $\rightarrow$ (ii)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$A.$ Proteins have peptide linkage

$B.$ Neucleic acid has Neucleotides
$C.$ Hydrolysis of cone sugar is inversion
$D.$ Starch is a polysaccharide.

Multiple choice biochemical polymers polymerisation chemistry

RNA molecules are of three types which are based on their different functions. These are:

  1. messenger RNA, translational RNA, structural RNA

  2. cytosine RNA, nucleoside RNA, nucleotide RNA

  3. messenger RNA, ribosomal RNA, transfer RNA

  4. primary RNA, secondary RNA, tertiary RNA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
There are 3 types of RNA, each encoded by its own type of gene:
mRNA - Messenger RNA $\rightarrow$ Encodes the amino acid sequence of a polypeptide.
tRNA - Transfer RNA $\rightarrow$ Brings amino acids to ribosomes during translation.
rRNA - Ribosomal RNA $\rightarrow$ With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.
Multiple choice biochemical polymers polymerisation chemistry

Maximum amount of RNA is found in:

  1. nucleolus.

  2. chloroplast.

  3. ribosomes.

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

Maximum amount of RNA is present in Nucleolus.

Nucleolus is present in Nucleus.

Multiple choice biochemical polymers polymerisation chemistry

When adenine is attached to ribose sugar, it is called adenosine. To make a nucleotide from it, it would require?

  1. Oxygenation

  2. Addition of a base

  3. Addition of phosphate

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

Answer:- (C) addition of phosphate

Adenine forms adenosine, a nucleoside, when attached to ribose. It forms adenosine triphosphate (ATP), a nucleotide, when three phosphate groups are added to adenosine.

Multiple choice chemistry combustion extinguishing fire ways to control fire combustion, fuels and flame

A white solid $X$ reacts with dil.$HCl$ to give colourless gas which is used in fire extinguishers. The solid $X$ is:

  1. $NaCl$
  2. $CH _2COONa$
  3. $Na _2CO _3$
  4. $NaHCO _3$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sodium bicarbonate can be used for fire extinguishers purpose as it releases carbon dioxide. 


The following reaction takes place: 

$ NaHC{ O } _{ 3 }(X)\ +\ HCl\ \rightarrow \ NaCl\ +\ C{ O } _{ 2 }\ +\ { H } _{ 2 }O $

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

Multiple choice chemistry combustion extinguishing fire ways to control fire combustion, fuels and flame

Fire extinguisher's containing $CO _2$ is the best extinguisher.

  1. Because $CO _2$ being heavier than oxygen, covers the fire like a blanket
  2. Because $CO _2$ being heavier than oxygen, increase fire.
  3. Because $CO _2$ being leighter than oxygen, covers the fire like a blanket

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

For fires involving electrical equipment and inflammable material like petrol, carbon dioxide is the best extinguisher. Carbon dioxide being heavier than oxygen, covers the fire like a blanket. Since, the contact between the duel and oxygen is cut off, the fire is extinguished.

Multiple choice chemistry combustion extinguishing fire ways to control fire combustion, fuels and flame

How carbon dioxide is stored in the house to extinguish fire?

  1. It can store in the bottles

  2. It can store in the cylinders under high pressure

  3. It can store in canes

  4. It can not store in any form
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Carbon dioxide is being a gas can be store in cylinder's under high pressure like L.P.G.When released from the cylinder, carbon dioxide expands enormously in volume and cools down. So, it not only forms blanket around the fire, it also brings down the temperature of the fuel.

Multiple choice chemistry combustion extinguishing fire ways to control fire combustion, fuels and flame

Why electrical equipment on burning do not extinguished fire by water? 

  1. Water shows exothermic reaction with electrical equipment.

  2. Water conduct electricity with electrical equipment's.

  3. Water shows endothermic reaction.

  4. Water is a combustible substance.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Water conducts electricity with electrical equipment's. Hence the area under water is developed with electricity. Therefore water is not used to the extinguished fire caused by electrical equipment.


Hence, the correct option is $B$

Multiple choice chemistry combustion extinguishing fire ways to control fire combustion, fuels and flame

Fire extinguishers contain $H _{2}SO _{4}$ and:

  1. $NaHCO _{3}$ and $Na _{2}CO _{3}$
  2. $NaHCO _{3}$ solution
  3. $Na _{2}CO _{3}$
  4. $Ca _{2}CO _{3}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Soda-acid fire extinguishers work by reacting sulfuric acid with sodium bicarbonate (NaHCO3) to produce carbon dioxide gas, which displaces oxygen and puts out the fire. Option A is the standard chemical composition for this type of extinguisher.