391. DNA stands for _____.

1. Di Nucleic Acid
2. Deoxynucleic Acid
3. Diribonucleic Acid
4. Deoxyribonucleic Acid

Option “4” is correct
Deoxyribo nucleic acid (DNA) is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses.
392. The orange colour of carrot is because of –

1. It grows in the soil
2. Carotene
3. It is not exposed to sunlight.
4. The entire plant is orange in colour

Option “2” is correct
The orange colour of carrot is because of Carotene.
393. Snake venom is highly modified saliva containing _________.

1. Prototoxins
2. Neutrotoxins
3. Zootoxins
4. Electrotoxins

Option “3” is correct
Snake venom is highly modified saliva containing zootoxins which facilitates the immobilization and digestion of prey, and defends against threats. It is injected by unique fangs after a bite, and some species are also able to spit.
394. Heavy water is _________.

1. Monoterium oxide
2. Polyterium oxide
3. Deuterium oxide
4. Trisium oxide

Option “3” is correct
Heavy water (D2O), also called deuterium oxide, water composed of deuterium, the hydrogen isotope with a mass double that of ordinary hydrogen, and oxygen.
395. Which of the following elements has the lowest melting point?

1. Bromine
2. Zinc
3. Lead
4. Calcium

Option “1” is correct
Bromine has lowest melting point in the following.It has melting point of -7.2℃.
396. Ethane chemical formulae is _______________.

1. C2H6
2. C2H3oH
3. C2SHOH
4. None Of the above

Option “1” is correct
Ethane has chemical formulae is C2H6.
397. Ethane chemical formulae is _______________.Which of the following bonds are weakest in nature?

1. Single bond
2. Double bond
3. Triple bond
4. Hydrogen bond

Option “4” is correct
Hydrogen Bond is weakest bond between atoms.Occur in molecules that have covelent bonds. Sometimes the electrons are not equally shared; one atom tends to have an electron more often than the other atom. In this situation one atom of the molecule becomes partly negative and the other then becomes partly positive. This is especially common between water molecules.
398. In the following reaction, fill in the blank.

Acid + Base → _______ + Water
1. Carbon dioxide
2. Metal Oxide
3. Hydrogen Gas
4. Salt

Option “4” is correct
When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt. The H(+) cation of the acid combines with the OH(-) anion of the base to form water.
399. Zinc phosphide is commonly used as –

1. Fungicide
2. Herbicide
3. Rodenticide
4. Deodorant

Option “3” is correct
Zinc Phosphides is commonly used as Rodenticides. They are a category of pest control chemicals intended to kill rodents.
400. Aspirin is common name of –

1. Salicylic acid
2. Salicylate
3. Methyl salicylate
4. Acetyl salicylic acid

Option “4” is correct
Aspirin, also known as Acetyl Salicylic acid (ASA), is a medication used to treat pain, fever, or inflammation.

9 thoughts on “Chemistry”

  1. I Love chemical…it’s my favourite subject..mere iss mein se hmesha hi boht ache marks aate hai….and my interest is also in chemistry…

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top