Tag: chemistry

Questions Related to 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
biochemical polymers polymerisation chemistry

  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)

Show answer
Correct Option: C
Explanation:

$A.$ Proteins have peptide linkage

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

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

biochemical polymers polymerisation chemistry

  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

Show answer
Correct Option: C
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.

Maximum amount of RNA is found in:

biochemical polymers polymerisation chemistry

  1. nucleolus.

  2. chloroplast.

  3. ribosomes.

  4. cytoplasm.

Show answer
Correct Option: C
Explanation:

Maximum amount of RNA is present in Nucleolus.

Nucleolus is present in Nucleus.

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

biochemical polymers polymerisation chemistry

  1. Oxygenation

  2. Addition of a base

  3. Addition of phosphate

  4. Hydrogenation

Show answer
Correct Option: C
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.

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

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

  1. $NaCl$

  2. $CH _2COONa$

  3. $Na _2CO _3$

  4. $NaHCO _3$

Show answer
Correct Option: D
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 $\text{D}$

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

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

  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

Show answer
Correct Option: A
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.

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

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

  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

Show answer
Correct Option: B
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.

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

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

  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.

Show answer
Correct Option: B
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 $B$

We cannot use a fire extinguisher which involves _____ as a extinguishing substance.

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

  1. carbon dioxide

  2. baking soda

  3. foam

  4. petrol

Show answer
Correct Option: D
Explanation:

We cannot use petrol as a fire extinguisher, because petrol is a combustible liquid which on combustion produces a lot of heat energy. So petrol is not used to stop the fire.

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

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

  1. $NaHCO _{3}$ and $Na _{2}CO _{3}$

  2. $NaHCO _{3}$ solution

  3. $Na _{2}CO _{3}$

  4. $Ca _{2}CO _{3}$

Show answer
Correct Option: A